EMRFD Message Archive 8968

Message Date From Subject
8968 2013-08-16 07:15:37 Peter Parker Video of simple SSB phasing receiver
Here's a video of my second (simpler) phasing receiver, showing the sideband
rejection I'm getting. I use an N3ZI DDS signal gen and mobile phone to
align it.

http://www.youtube.com/watch?v=m_RFd5Yhe8c

One thing I didn't realise before is that the setting of the RF phase shift
control interacted with the audio frequency at which best image rejection
was achieved.

This was noted at 500, 1000 and 2000 Hz and probably higher (not tested).
The null was sharper at higher frequencies than lower frequencies.

This may mean that it's an advantage if it's made variable via a front panel
pot to null out QRM from signals on the opposite sideband that should be
rejected.

This would be particularly useful for a CW receiver. Although there is
another school of thought that favours fixed resistors etc as they are more
reliable than potentiometers.

Note that my first receiver has better audio filtering, including two back
to back 1k - 8 ohm transformers and a good LPF in the 8 ohm parts. So it
doesn't have the 5 kHz problem this has. Still for something with just 3
transistors + 1 audio IC I'm very pleased with how it's turned out.

73, Peter VK3YE
8969 2013-08-16 11:46:26 Leonard Re: Video of simple SSB phasing receiver
Nice video!. Interesting applicati
8973 2013-08-17 05:15:08 Nick Kennedy Re: Video of simple SSB phasing receiver
That was pretty amazing - single signal reception and only two transistors
and an LM386.

I did quite a few searches on SP5AHT but wasn't able to find a schematic
(of the receiver part). Although the video explains the design in a block
diagram way, it would be interesting to see your circuit.

73-

Nick, WA5BDU


[Non-text portions of this message have been removed]
8974 2013-08-17 07:38:19 Paul Daulton Re: Video of simple SSB phasing receiver
Nick check out .avt.pl/photo/_avt2906.pdf (google it)text not in english .

Paul k5ms

Quoting Nick Kennedy :

That was pretty amazing - single signal reception and only two transistors
and an LM386.

I did quite a few searches on SP5AHT but wasn't able to find a schematic
(of the receiver part). Although the video explains the design in a block
diagram way, it would be interesting to see your circuit.

73-

Nick, WA5BDU

[Non-text portions of this message have been removed]


Paul Daulton K5WMS
beacon WMS 185.302 khz qrss30/slow 24/7
Jacksonville,Ar 72076
em34wu



[Non-text portions of this message have been removed]
8975 2013-08-17 15:38:06 jor Re: Video of simple SSB phasing receiver
Nice VIDEO Peter,
It is hard to get an linear suppressi
8978 2013-08-18 08:49:14 Jam Video of simple SSB phasing receiver
Hi,To my knowledge SP5AHT had published one article "TinySSB 80m"- 80M
ssb transceiver using phasing technique- in Polish magazine['Elektronica
dla Wszystkich' nr 7/2009]. The circuit diagram and essentials details
are available
athttp://www.sp-qrp.pl/modules.php?name=Content&pa=showpage&pid=49
<http://www.sp-qrp.pl/modules.php?name=Content&pa=showpage&pid=49>
Jam - VU2RQ



[Non-text portions of this message have been removed]
8979 2013-08-18 10:48:24 Paul Daulton Re: Video of simple SSB phasing receiver
I found the article , wish I could find English translation

Paul k5wms

Quoting Jam

:

Hi,To my knowledge SP5AHT had published one article "TinySSB 80m"- 80M
ssb transceiver using phasing technique- in Polish magazine['Elektronica
dla Wszystkich' nr 7/2009]. The circuit diagram and essentials details
are available
athttp://www.sp-qrp.pl/modules.php?name=Content&pa=showpage&pid=49

Jam - VU2RQ

[Non-text portions of this message have been removed]


Paul Daulton K5WMS
beacon WMS 185.302 khz qrss30/slow 24/7
Jacksonville,Ar 72076
em34wu




[Non-text portions of this message have been removed]
8980 2013-08-18 12:00:19 Mike Article translation (was: Video of simple SSB phasing receiver)
I also found the article to be fascinating, so much so that I had to
figure out how to get a translation. I used Google Translation:

******* begin excerpt translation

Among the various radio emission bands dominated by short-wave
single-sideband modulation for years (SSB stands for Single Side Band).
By sending only one sideband (top - bottom USB - LSB) of suppression
the carrier wave is obtained by a significant saving power and
bandwidth. it is Specific modulation amplitude, wherein all power SSB
transmitter is used to produce only one sideband. The transmitter is a
narrower band of frequencies, which allows you to work more stations in
the band of the same width. the turn narrowing of about 50% bandwidth
received receiver gives you additional profit an improvement in the
ratio of the received signal to-noise ratio (about 3dB at the output of
the receiver). However, none of the carrier makes it possible to clear
reception of distant signals several hundred hertz from another SSB
signal. These benefits are paid for SSB complication of
transmitter-receivers, or transceiver.

There are two ways to obtain the signal jednowstęgowego: a method of
filtering and phase. In this method, filtering, commonly used and
repeatedly EdW described in, for example, when presentation sucks
Minitransceiver Antek suppression of the carrier wave occurs in the
modulator balanced, and the cutout of the web side and further
suppression of the carrier is in a properly tuned quartz filter.
The method does not use phase the filters, but by adding or subtracting
from each other respectively formed signals from the balanced modulators
receives a ribbon top or bottom. quality SSB signal forming in this
process, the due to difficulties in the implementation of broadband
shifters, is worse. because
This method is rarely used in practice. Since the signal can be formed
SSB directly on the operating frequency (direct frequency conversion)
and the devices are not too complicated and the cost of low, so this is
temptation for beginners or experimenting electronics - radio amateurs.

You should know that the direct conversion of is also used in devices
SDR, the Software Defined Radio, which - thanks to technology, software
- are significantly cheaper than hardware - Hardware stuff. However,
they require access to the computer, and that in many cases can be a
disadvantage. Recently, the direct the frequency of transformation by
SSB phase has made a lot of progress. They were developed digital
modulator / detectors (e.g. Talyora) and the ease of access to
components conducive to the implementation of such a modernized systems,
such as the use of DDS generators. A good example Here is a Russian
design Minitransceiver Piligrim, widely described websites.

We offer the given at the beginning of something much simpler -
transceiver TinySSB as an updated version of Minitransceiver
phase-homodynowego, built for the first time by in the 80's the last
century. The author is convinced that the in and out Such a simple
design Minitransceiver SSB low power has a lot to learn. It can be an
exercise before construction much more complex and much expensive, for
example, said piligrim and with a good antenna and the favorable
propagation ensure normal communication, not only local, in the popular
band 80m.

How does it work? Working device name comes TinySSB the fact that the
system operates with a simple method phase, which - in comparison with
the method Filtrowa - Characterized primarily lower sideband
suppression, and therefore slightly worse signal quality
jednowstęgowego, hence the "thin" SSB.

Block diagram of the present Minitransceiver, explaining the working
principle and RF signal routing during commissioning and transmission
(RX and TX), shown in Figure 1. The device uses a system of direct
transformation, or "homodyne receiver." In such a receiver coming out
of antenna radio signal, audio, VSB
Telegraphic SSB or CW, is demodulated in a mixer, which occurs a local
oscillator signal. generator VFO is in the working band, and the the
frequency is shifted by a distance that allows received signal. While
working as a broadcast mixer modulator and signal formation occurs Also
the frequency of operation. the signal from the
microphone after amplification, is fed jednowstęgowego to the mixer,
wherein is suppressing the carrier frequency and the second sideband.
frequency The output frequency is equal to the difference low frequency
signal generator and Mixing VSB both during collection and transmission
transmits the lower sideband, and suppresses the upper web and a carrier
wave.

This system works in two directions, without need to switch from
analogue to Receiving - change transmission lines RF signals and LF
Thus, in addition to economy of construction, achieved the elimination
of the phenomenon dwusygnałowego reception which occurs almost all
previously described receivers for direct
frequency conversion.

The system is limited to the essential minimum, and the design Device
author has adopted a policy to system contains elements of home
inventory, including the popular transistors, and no integrated
circuits, using cheap multimedia kit with headphones equipped with power
regulator Voice merged with a microphone, and
switching from reception to broadcast in the easiest way, or by changing
the the voltage switch on the front panel.

Basic parameters Minitransceiver:
- Operating frequency: 3500 ... 3800kHz (May be limited to logging audio
bandwidth)
- Issue: SSB (LSB)
- Receiver sensitivity: about 3μV the 10dB S + N / N,
- Output power: 0.3-0.5 W,
- Unwanted sideband suppression: 20 .. 30dB,
- Carrier wave attenuation:> 30dB
- Power supply voltage: 12 V (13.8 V)
- Sample size PCB: 115 x 115mm.

Schematic diagram is shown Figure 2. The antenna signal by diode D2
connector, polarized in the direction of the pass diode, is indicated on
the controller RF - muffler antenna acting as the controller received
signal strength. after the initial filtered in a serial circuit LC (10μH
+ 180pF) is directed the amplifier circuit transistor OE T4. This
system, like and the LED are powered only when receiving. The main RF
signal filtering of the band 80m provides a resonant circuit L2C9 tuned
to the center of SSB. The output this circuit, by coupling coil, is
included in the RF phase shifter in simplest form, namely in the form of
two-terminal circuit R6-C 10. The values ​​of these elements are so
selected such that the mid-band gain SSB signal phase shift of 90 ° (+45
and -45) and consequently damps the upper web side, because in the 80m
band used the lower band (LSB). These signals are then fed to two mixers
balanced on the diodes D4-D5 and D6-D7 where they are mixed with the
signal tuned VFO generator. In one half-cycle this voltage keying leads
one pair of diodes, and the other second pair. As a result, produces two
small signal components frequencies that by glands DL4 and DL5 are
directed to the simplest shifters LF phase the elements C27, R17 and
R18, C28, and C25, C26 punch remnants of the RF signal, and then are
added a bifilar winding L6 and through the filter LF demodulated signal
is supplied to the audio amplifier. With this combination of elements RC
is obtained as a result of a low frequency signal The second band,
mixing symmetrically set in relation to the carrier frequency, is
largely suppressed.

The main reception is dependent selectivity low pass filter, comprising
which includes coil L7 and capacitors C33 and C35. Its purpose is to
suppress 3 kHz-band signals. The filtered LF signal is then strengthened
in a two-stage system OE transistor T9 and T8. The final signal Mw by T7
emitter is fed through a capacitor C31 to the socket headset.
Reinforcing the point, and the power supply is optimized for handsets
multimedia, which windings are parallel. The signal frequency received,
and also transmitted, is determined by the frequency of VFO generator.
Its value in the main mainly determines the resonant circuit coil L4 and
the resultant value of the capacitance capacitors, mainly C19.
Capacitors C22 and C23 provide positive feedback Feedback necessary to
operate the generator transistor T5. VFO signal is then amplified in a
transistor circuit T6 and L5 fed by a transformer the mixer VSB. In
order to phase shift signal coil windings are tryfilarnie wound, or
three wires simultaneously. Tunable frequency VFO is done using the LED
capacitive D3 (BB130) by changing the voltage potentiometer P1. In the
model system, the slider of the potentiometer is set at extreme
positions (minimum and maximum voltage across the diode), obtained
tunable Device approximately 300kHz, from about 3.5-3.8 MHz. Because
comfort tuning receiver depends precisely on this potentiometer, you
should use a potentiometer Multi-turn.

Depending on the value of the applied LC circuit and lights, you can get
another
frequency range. By trying to do with easily BB105 available LEDs, give
scope retuning of about 50 kHz, which can satisfy many designers who
want to reduce work only to the most active segment of SSB.

When using ceramic capacitors with black stripe, and styrofleksowych
with a black dot or the letter J, the stability of the generator was
very high, there was no need
for additional compensation systems, the more PLL, not to mention DDS,
which themselves are more complicated and more expensive than the
proposed device.

The entire unit can be powered 12 V (13.8 V) with power well stabilized
or 12V battery. system US1 - 7808 stabilizes the supply voltage 8V and
is used to power the VFO. Switching the device from receiving the
broadcast (RX / TX) is performed by changing the voltage, which was
conducted by through the switch PZ fixed on the front of the
Minitransceiver. Of course you can use a relay, which the coil is
activated by pressing the PTT.

While transmitting low frequency signal with microphone electret Me is
strengthening OE in the system of the transistor T10, and then is given
to the team mixer jednowstęgowego, which is now used in the opposite
direction than the reception. First, the signal is reduced 3kHz within
the scope of a low-pass filter, then it is separated into L6 two signals
out of phase and given the LF phase shifters, where goes to balanced
mixer unit D4, D5 and D6, D7. With the additional knobs P3 and P4 can be
exactly offset modulators and optimum damping carrier. The author used
multi-turn potentiometer assembly. final transmitter signal, after
passing through the shifter RF phase is obtained at the output tapped
coil L2 is deprived only the carrier, but also significantly suppress
the sideband.

A comprehensive explanation of how it works, the VSB mixer, which in our
the lower sideband is passed, and suppresses the upper and carrier wave
can be demonstrated the vector diagram - would show how the indi signals
adding the phase relation and in phase opposition deduct, but due to
limited amount of these illustrations have been omitted. Further
strengthening the SSB signal is OE in the system of the transistor T3.
then the signal through impedance matching emitter of T2 goes to input
amp transistor BD135. Operating point of the transistor provides
throughput polarized rectifying diode D1, which builds up tension about
0.6 V. An emitter resistor is used to stabilize the degree of heat and
improves linearity degree. With so selected values emitter current is
approximately 15mA. Load level L1 coil is wound bifilar pattern (1:4
impedance transformation). The output of the transmitter is directed by
isolating capacitor C4 aerial socket. Inductor L1 is not only matches
the impedance of the output stage, but with capacitor C1 form a circuit
resonance for 80m, which further not only filters the output signal, but
also input during the reception. The model output power of the system
was about 300mW, and with a loud gwizdnięciu into the microphone even
exceed 500mW. The best results obtained by using Transistor 2SC3420.

Installation and commissioning The entire system can be described
Minitransceiver assembled using universal PCB. The plate (Figure 3) can
be obtained by etching or milling soldering islands, while is the mass
of the remaining layer. technology this is used to solve specifically
because it gives the possibility to changes, ease of testing, sampling
different variants of the arrangement, which would be difficult at the
"closed" the PCB. There is also a the ability to use older components,
with larger dimensions (without prejudice to signal quality and target
parameters device).

Shown in the first photograph plate prints from the book's "Amateur
radio structures for Beginners" (WKiŁ 1994) and is a bit of an
overstatement, because it is slightly larger and has a few more islands
to be able to add one transistor of the amplifier a microphone and
amplifier the transmitter end. The chip itself is installed quickly and
easily, but only by prior preparation of plates - Cleaning the copper
layer and cover pobieleniu rosin or the entire surface, and preparing
and checking the LC circuit.

Realizing that a novice designers most problems can just make the
correct execution of the winding, this subject need to spend a little
more space. As the coil can DL1-DL5 use concentric coils factory
resembling resistors, and you Note that the first of them, the DL1, was
at a higher current load, such as 1A, wherein the inductance value is
not are critical. It is best to use a choke 22μH/1A factory. You can
also rewind winding the 6-hole ferrite core F-200. DL3 must form a
resonant circuit a capacitor C14 for approximately 3.7 MHz (With a
typical value of the capacitor falls 10μH 180pF). If you use the choke
4.7 μH, the value of the capacitor will be greater and should be 420pF.
Coils of filters on range of 80 m can be wound on toroidal cores, eg
type Amidon T37-2 (red; 9.53 x 5.21 x 3.25 mm, Al. = 4). Coil L2 should
contain 36 turns of wire DNE 0.4 (unhook the sixth reel from the ground)
the wound on the coupling coil L3 - 10 turns of the same wire or jumpers
phone. VFO coil circuit, or L4 should contain 26 turns of wire DNE 0.4
on the same core. In the case of filter L1 coil has 36 turns, but it
should be it wound bifilar pattern, or two wires at the same time, after
18 turns of wire DNE 0.4. With a different core than the T37-2, should
be convert coils, taking into account the different number of AL current
core (AL - number of turns per 1nH). Wideband transformer feeding the
VFO signal to the mixer, designated as L5, should include three windings
wound simultaneously at 10 DNE 0.4 turns on the core FT37-43 or
RP10x6x3. This core and T37-2 is available in AVT. Other low-frequency
filter should be wound around the core goblet (two elements of the
M-shaped, and in the middle plastic spool for winding), but with a
little luck, you can find ready winding matching our solution.
Inductance may slightly vary from the above and then you have to adjust
the volume. Autotransformer LF, adder, marked As L6 can be wound bifilar
pattern after about 400 turns of wire DNE 0.1 per cup core 14mm diameter
material F 1001 and AL = 400 You can also try to use transformer from an
old transistor radio with two symmetrically wound windings. Creates a
choke coil L7 factory with an inductance of about 100mH, which can be
obtained by winding coils 500 DNE wire 0.1 on the cup core diameter 14mm
material F 1001 and Al = 400, 250 turns to the AL = 1600. It is worth to
look for the Internet offer of such reactors because sometimes you can
buy them at a price of 1 ... 2 zł.

The manuscript winding, including and the above case, it is preferable
to select a core of higher value AL, because then reduce the number of
coils and windings. You can wrap the thicker wire. as you can see in the
pre-applied by cores slightly larger overall dimensions of diameter of
about 26mm, because that happened to be in a drawer. A few practical
considerations regarding the windings on ferrite cores. It is good to
have something to measure inductance coils: first, the lack of an
ohmmeter break, and then measure the inductance; RF coil for example, by
using the supplied to the multimeter. All windings it is protected by
varnishing waterproof adhesive or glue. After drying again inductance
check to see if you need to change the value of the capacitor
cooperating with winding. Coils for goblet cores may vary inductance
Depending on the change in the gap. Here we try to change the gap, eg by
inserting a thin plastic film or thin paper, because in this way you can
match the required inductance. Also too strong compression screw core
mounting changes inductance, not to mention that the mere fact of its
inclusion in the hole it can have a big impact. author used screws M2, 5
brass, which caused only the minimum detuning coils, as opposed to steel.

Commissioning of the system is dependent on the possession measurement
capability. Now you will be given simple methods with minimal feature:
when elements are already soldered to the plate, you need a voltmeter
Check the DC voltages the electrodes of transistors, as it may be that
the significant rozrzutach gain transistors - you need to adjust
resistor values ​​in the database. It is best to run after mounting
electronic part assembling the selected housing plate metal or made ​​by
hand. The the simplest case, the cover may be two pieces of bent
aluminum sheet in the shape of a flattened U. On the front panel should
be installed potentiometers P1 and P2 and Pz switch, and a jack socket
for connecting a set of słuchawkowo-mic. It is to provide the front wall
in the scale email. In this case, it may be any digit frequency meter,
even working only to 4MHz. The rear wall should include a power outlet
and antenna. Also, the back of the can BD135 transistor bolted, but by
Mica washer, if the collector is uncovered.

Running is best to start VFO, or by checking the voltage at the emitter
T5, which should be about 4V and the emitter of T6, which may be in the
range of 200-500mV. When setting Pz receiving position, the voltage at
the collector T4, T9 and T8 should be close to half power supply, or up
to about 6V, identically broadcasting with the T3 and T10. also around
half of the supply voltage should appear on the emitters T7 (on
delivery) and T2 (in broadcasting). Current of the transistor T1 You can
also check by measuring voltage drop across the emitter resistor. The
quiescent voltage across the resistor T1 may be in the range 15-25mV.
Its value is affected by light D1 and a resistor R2 (can, if necessary,
change their values). Another necessary step is to check VFO with a
multimeter frequency or extra receiver
for 80m close to the output of the system.

The author in his prototype model, although Designed primarily for
experiments, used a hand-constructed microprocessor digital scale
AVT-5112, connected T6 to the collector via a capacitor 3.9 pF, and the
previous connection to the emitter of the larger capacity resulted in
slight interference to. Such a scale is a very useful equipment Not only
this transceiver. You should know that too retuning a wide range of
generator can be limited by additional resistors connected to extreme
terminal potentiometer. The correct VFO is provided additional capacitor
C20 and the beginning of this can be a trimmer a 30-50pF. If the
generator is running in its own sphere, and the coils were checked eg by
GDO (TDO), then you connect the antenna headphones you can pick up local
stations operating slightly above the 3.7 MHz.

Checking the receiver and its refinement best done using a generator
RF with adjustable output level signal, but the reception quality
correction should be made during good propagation played in the
competition, because then you will definitely hear a lot of stations and
you will be able to improve the system. certainly You can then test the
silencer P2 and improve the sensitivity of the correction values
capacitor C9. You can also choose frequency response of a low-frequency
circuit by adjusting the values ​​of capacitors LF amplifier For
example, in a You can easily narrow band track LF by a small increase in
capacity C33 or C35, and by attaching the resistors R21 and R23
additional capacitors with selected values ​​in the range 330pF ... 1nF.
Such negative feedback Feedback will also to some extent bandwidth
limitation of the top.

Also noticeable improvement in reception, including the partial
elimination of the distortion-band, it can bring to join a capacitor
with a value selected from the range 22nF 10nF ... to the coil L7 -
foundation parallel resonant circuit enhancer attenuation above 3kHz. So
let's experiment to adjust the audio to your liking. The output of the
transmitter, and attached Pz the broadcast, you can check through
additional receiver close the antenna output resistor loaded 50Ω/1W and
oscilloscope, or diode probe. In the simplest case, it may to be a light
bulb 6V bike / 0.6 W, which, thanks zaświecaniu modulation in time will
ensure that most transmitter amplifier is working properly.

One of the necessary steps for run the transmitter is to balance
modulator through the sliders potentiometers P3 and P4, the output pins
the lowest level of the carrier. to this action is best to use a
receiver outside, although the setting with RF probe the smallest signal
level RF will be correct. It should be noted that the diodes modulator
does not necessarily have to be matched quartet, but they must be of the
same series. It is worth more to choose such a close parameters, such as
using a multimeter by measuring the voltage drop across the junction. on
switching to an external receiver web USB side can try to choose
elements mentioned above shifters RF phase and LF for as little unwanted
signal level of the web, but This activity requires a lot of
experimentation and experience. In order to change sideband In our
system, you must cross to bring phase shift signals.

In Figure 4 is shown a sketch sheet Minitransceiver bandwidth. It can
easily be seen on the shifter LF phase gives a phase shift equal to Only
90 ° at a frequency of about 700Hz and 1.5 kHz, as at points A and B
attenuation the second web is about 30dB (better characteristics can be
achieved in a method on filter with a simple filter frequency). Despite
the above mentioned drawbacks and low-power transmitter with a good an
antenna (for example, the dipole 2 x 19.5 m) may be - with good
propagation conditions - make in this minitransceiverze not TinySSB only
home communications 80m band. More experienced engineers author
encourages the modernization of equipment, for example, by replacing the
diode modulator team keys on a digital system (74HC4066, 74HC4053 ...)
and amplifiers popular transistor amplifiers operating with the
formation of characteristic Mw, and share all comments on the operation.

Andrew Janeczek
sp5aht@swiatradio.com.pl

selected parts list translation:

L1 2x18 turns on T37 0.4 DNE-2 (perhaps T37-2?)
(about 5.3 μH)
L2 36 turns on T37 0.4 (perhaps T37-2?)
L3 10 turns on L2 DNE 0.4
L4 26 turns DNE 0.4 on T37-2 (2.8 uh)
L5 3 x 10 turns DNE 0.4 on FT37-43
L6 2 x 400 turns DNE 0.1 on F1001 (Al=400) approx. 250 mh
L7 500 turns DNE 0.1 on F1001 (Al=400) approx. 100 mh

*********** end of excerpt of translation

8981 2013-08-18 12:26:40 Paul Daulton Re: Article translation (was: Video of simple SSB phasing receiver)
Thanks Mike this is a valuable reference.

Paul k5wms

Quoting Mike :

I also found the article to be fascinating, so much so that I had to
figure out how to get a translation. I used Google Translation:

******* begin excerpt translation

Among the various radio emission bands dominated by short-wave
single-sideband modulation for years (SSB stands for Single Side Band).
By sending only one sideband (top - bottom USB - LSB) of suppression
the carrier wave is obtained by a significant saving power and
bandwidth. it is Specific modulation amplitude, wherein all power SSB
transmitter is used to produce only one sideband. The transmitter is a
narrower band of frequencies, which allows you to work more stations in
the band of the same width. the turn narrowing of about 50% bandwidth
received receiver gives you additional profit an improvement in the
ratio of the received signal to-noise ratio (about 3dB at the output of
the receiver). However, none of the carrier makes it possible to clear
reception of distant signals several hundred hertz from another SSB
signal. These benefits are paid for SSB complication of
transmitter-receivers, or transceiver.

There are two ways to obtain the signal jednowstęgowego: a method of
filtering and phase. In this method, filtering, commonly used and
repeatedly EdW described in, for example, when presentation sucks
Minitransceiver Antek suppression of the carrier wave occurs in the
modulator balanced, and the cutout of the web side and further
suppression of the carrier is in a properly tuned quartz filter.
The method does not use phase the filters, but by adding or subtracting
from each other respectively formed signals from the balanced modulators
receives a ribbon top or bottom. quality SSB signal forming in this
process, the due to difficulties in the implementation of broadband
shifters, is worse. because
This method is rarely used in practice. Since the signal can be formed
SSB directly on the operating frequency (direct frequency conversion)
and the devices are not too complicated and the cost of low, so this is
temptation for beginners or experimenting electronics - radio amateurs.

You should know that the direct conversion of is also used in devices
SDR, the Software Defined Radio, which - thanks to technology, software
- are significantly cheaper than hardware - Hardware stuff. However,
they require access to the computer, and that in many cases can be a
disadvantage. Recently, the direct the frequency of transformation by
SSB phase has made a lot of progress. They were developed digital
modulator / detectors (e.g. Talyora) and the ease of access to
components conducive to the implementation of such a modernized systems,
such as the use of DDS generators. A good example Here is a Russian
design Minitransceiver Piligrim, widely described websites.

We offer the given at the beginning of something much simpler -
transceiver TinySSB as an updated version of Minitransceiver
phase-homodynowego, built for the first time by in the 80's the last
century. The author is convinced that the in and out Such a simple
design Minitransceiver SSB low power has a lot to learn. It can be an
exercise before construction much more complex and much expensive, for
example, said piligrim and with a good antenna and the favorable
propagation ensure normal communication, not only local, in the popular
band 80m.

How does it work? Working device name comes TinySSB the fact that the
system operates with a simple method phase, which - in comparison with
the method Filtrowa - Characterized primarily lower sideband
suppression, and therefore slightly worse signal quality
jednowstęgowego, hence the "thin" SSB.

Block diagram of the present Minitransceiver, explaining the working
principle and RF signal routing during commissioning and transmission
(RX and TX), shown in Figure 1. The device uses a system of direct
transformation, or "homodyne receiver." In such a receiver coming out
of antenna radio signal, audio, VSB
Telegraphic SSB or CW, is demodulated in a mixer, which occurs a local
oscillator signal. generator VFO is in the working band, and the the
frequency is shifted by a distance that allows received signal. While
working as a broadcast mixer modulator and signal formation occurs Also
the frequency of operation. the signal from the
microphone after amplification, is fed jednowstęgowego to the mixer,
wherein is suppressing the carrier frequency and the second sideband.
frequency The output frequency is equal to the difference low frequency
signal generator and Mixing VSB both during collection and transmission
transmits the lower sideband, and suppresses the upper web and a carrier
wave.

This system works in two directions, without need to switch from
analogue to Receiving - change transmission lines RF signals and LF
Thus, in addition to economy of construction, achieved the elimination
of the phenomenon dwusygnałowego reception which occurs almost all
previously described receivers for direct
frequency conversion.

The system is limited to the essential minimum, and the design Device
author has adopted a policy to system contains elements of home
inventory, including the popular transistors, and no integrated
circuits, using cheap multimedia kit with headphones equipped with power
regulator Voice merged with a microphone, and
switching from reception to broadcast in the easiest way, or by changing
the the voltage switch on the front panel.

Basic parameters Minitransceiver:
- Operating frequency: 3500 ... 3800kHz (May be limited to logging audio
bandwidth)
- Issue: SSB (LSB)
- Receiver sensitivity: about 3μV the 10dB S + N / N,
- Output power: 0.3-0.5 W,
- Unwanted sideband suppression: 20 .. 30dB,
- Carrier wave attenuation:> 30dB
- Power supply voltage: 12 V (13.8 V)
- Sample size PCB: 115 x 115mm.

Schematic diagram is shown Figure 2. The antenna signal by diode D2
connector, polarized in the direction of the pass diode, is indicated on
the controller RF - muffler antenna acting as the controller received
signal strength. after the initial filtered in a serial circuit LC (10μH
+ 180pF) is directed the amplifier circuit transistor OE T4. This
system, like and the LED are powered only when receiving. The main RF
signal filtering of the band 80m provides a resonant circuit L2C9 tuned
to the center of SSB. The output this circuit, by coupling coil, is
included in the RF phase shifter in simplest form, namely in the form of
two-terminal circuit R6-C 10. The values ​​of these elements are so
selected such that the mid-band gain SSB signal phase shift of 90 ° (+45
and -45) and consequently damps the upper web side, because in the 80m
band used the lower band (LSB). These signals are then fed to two mixers
balanced on the diodes D4-D5 and D6-D7 where they are mixed with the
signal tuned VFO generator. In one half-cycle this voltage keying leads
one pair of diodes, and the other second pair. As a result, produces two
small signal components frequencies that by glands DL4 and DL5 are
directed to the simplest shifters LF phase the elements C27, R17 and
R18, C28, and C25, C26 punch remnants of the RF signal, and then are
added a bifilar winding L6 and through the filter LF demodulated signal
is supplied to the audio amplifier. With this combination of elements RC
is obtained as a result of a low frequency signal The second band,
mixing symmetrically set in relation to the carrier frequency, is
largely suppressed.

The main reception is dependent selectivity low pass filter, comprising
which includes coil L7 and capacitors C33 and C35. Its purpose is to
suppress 3 kHz-band signals. The filtered LF signal is then strengthened
in a two-stage system OE transistor T9 and T8. The final signal Mw by T7
emitter is fed through a capacitor C31 to the socket headset.
Reinforcing the point, and the power supply is optimized for handsets
multimedia, which windings are parallel. The signal frequency received,
and also transmitted, is determined by the frequency of VFO generator.
Its value in the main mainly determines the resonant circuit coil L4 and
the resultant value of the capacitance capacitors, mainly C19.
Capacitors C22 and C23 provide positive feedback Feedback necessary to
operate the generator transistor T5. VFO signal is then amplified in a
transistor circuit T6 and L5 fed by a transformer the mixer VSB. In
order to phase shift signal coil windings are tryfilarnie wound, or
three wires simultaneously. Tunable frequency VFO is done using the LED
capacitive D3 (BB130) by changing the voltage potentiometer P1. In the
model system, the slider of the potentiometer is set at extreme
positions (minimum and maximum voltage across the diode), obtained
tunable Device approximately 300kHz, from about 3.5-3.8 MHz. Because
comfort tuning receiver depends precisely on this potentiometer, you
should use a potentiometer Multi-turn.

Depending on the value of the applied LC circuit and lights, you can get
another
frequency range. By trying to do with easily BB105 available LEDs, give
scope retuning of about 50 kHz, which can satisfy many designers who
want to reduce work only to the most active segment of SSB.

When using ceramic capacitors with black stripe, and styrofleksowych
with a black dot or the letter J, the stability of the generator was
very high, there was no need
for additional compensation systems, the more PLL, not to mention DDS,
which themselves are more complicated and more expensive than the
proposed device.

The entire unit can be powered 12 V (13.8 V) with power well stabilized
or 12V battery. system US1 - 7808 stabilizes the supply voltage 8V and
is used to power the VFO. Switching the device from receiving the
broadcast (RX / TX) is performed by changing the voltage, which was
conducted by through the switch PZ fixed on the front of the
Minitransceiver. Of course you can use a relay, which the coil is
activated by pressing the PTT.

While transmitting low frequency signal with microphone electret Me is
strengthening OE in the system of the transistor T10, and then is given
to the team mixer jednowstęgowego, which is now used in the opposite
direction than the reception. First, the signal is reduced 3kHz within
the scope of a low-pass filter, then it is separated into L6 two signals
out of phase and given the LF phase shifters, where goes to balanced
mixer unit D4, D5 and D6, D7. With the additional knobs P3 and P4 can be
exactly offset modulators and optimum damping carrier. The author used
multi-turn potentiometer assembly. final transmitter signal, after
passing through the shifter RF phase is obtained at the output tapped
coil L2 is deprived only the carrier, but also significantly suppress
the sideband.

A comprehensive explanation of how it works, the VSB mixer, which in our
the lower sideband is passed, and suppresses the upper and carrier wave
can be demonstrated the vector diagram - would show how the indi signals
adding the phase relation and in phase opposition deduct, but due to
limited amount of these illustrations have been omitted. Further
strengthening the SSB signal is OE in the system of the transistor T3.
then the signal through impedance matching emitter of T2 goes to input
amp transistor BD135. Operating point of the transistor provides
throughput polarized rectifying diode D1, which builds up tension about
0.6 V. An emitter resistor is used to stabilize the degree of heat and
improves linearity degree. With so selected values emitter current is
approximately 15mA. Load level L1 coil is wound bifilar pattern (1:4
impedance transformation). The output of the transmitter is directed by
isolating capacitor C4 aerial socket. Inductor L1 is not only matches
the impedance of the output stage, but with capacitor C1 form a circuit
resonance for 80m, which further not only filters the output signal, but
also input during the reception. The model output power of the system
was about 300mW, and with a loud gwizdnięciu into the microphone even
exceed 500mW. The best results obtained by using Transistor 2SC3420.

Installation and commissioning The entire system can be described
Minitransceiver assembled using universal PCB. The plate (Figure 3) can
be obtained by etching or milling soldering islands, while is the mass
of the remaining layer. technology this is used to solve specifically
because it gives the possibility to changes, ease of testing, sampling
different variants of the arrangement, which would be difficult at the
"closed" the PCB. There is also a the ability to use older components,
with larger dimensions (without prejudice to signal quality and target
parameters device).

Shown in the first photograph plate prints from the book's "Amateur
radio structures for Beginners" (WKiŁ 1994) and is a bit of an
overstatement, because it is slightly larger and has a few more islands
to be able to add one transistor of the amplifier a microphone and
amplifier the transmitter end. The chip itself is installed quickly and
easily, but only by prior preparation of plates - Cleaning the copper
layer and cover pobieleniu rosin or the entire surface, and preparing
and checking the LC circuit.

Realizing that a novice designers most problems can just make the
correct execution of the winding, this subject need to spend a little
more space. As the coil can DL1-DL5 use concentric coils factory
resembling resistors, and you Note that the first of them, the DL1, was
at a higher current load, such as 1A, wherein the inductance value is
not are critical. It is best to use a choke 22μH/1A factory. You can
also rewind winding the 6-hole ferrite core F-200. DL3 must form a
resonant circuit a capacitor C14 for approximately 3.7 MHz (With a
typical value of the capacitor falls 10μH 180pF). If you use the choke
4.7 μH, the value of the capacitor will be greater and should be 420pF.
Coils of filters on range of 80 m can be wound on toroidal cores, eg
type Amidon T37-2 (red; 9.53 x 5.21 x 3.25 mm, Al. = 4). Coil L2 should
contain 36 turns of wire DNE 0.4 (unhook the sixth reel from the ground)
the wound on the coupling coil L3 - 10 turns of the same wire or jumpers
phone. VFO coil circuit, or L4 should contain 26 turns of wire DNE 0.4
on the same core. In the case of filter L1 coil has 36 turns, but it
should be it wound bifilar pattern, or two wires at the same time, after
18 turns of wire DNE 0.4. With a different core than the T37-2, should
be convert coils, taking into account the different number of AL current
core (AL - number of turns per 1nH). Wideband transformer feeding the
VFO signal to the mixer, designated as L5, should include three windings
wound simultaneously at 10 DNE 0.4 turns on the core FT37-43 or
RP10x6x3. This core and T37-2 is available in AVT. Other low-frequency
filter should be wound around the core goblet (two elements of the
M-shaped, and in the middle plastic spool for winding), but with a
little luck, you can find ready winding matching our solution.
Inductance may slightly vary from the above and then you have to adjust
the volume. Autotransformer LF, adder, marked As L6 can be wound bifilar
pattern after about 400 turns of wire DNE 0.1 per cup core 14mm diameter
material F 1001 and AL = 400 You can also try to use transformer from an
old transistor radio with two symmetrically wound windings. Creates a
choke coil L7 factory with an inductance of about 100mH, which can be
obtained by winding coils 500 DNE wire 0.1 on the cup core diameter 14mm
material F 1001 and Al = 400, 250 turns to the AL = 1600. It is worth to
look for the Internet offer of such reactors because sometimes you can
buy them at a price of 1 ... 2 zł.

The manuscript winding, including and the above case, it is preferable
to select a core of higher value AL, because then reduce the number of
coils and windings. You can wrap the thicker wire. as you can see in the
pre-applied by cores slightly larger overall dimensions of diameter of
about 26mm, because that happened to be in a drawer. A few practical
considerations regarding the windings on ferrite cores. It is good to
have something to measure inductance coils: first, the lack of an
ohmmeter break, and then measure the inductance; RF coil for example, by
using the supplied to the multimeter. All windings it is protected by
varnishing waterproof adhesive or glue. After drying again inductance
check to see if you need to change the value of the capacitor
cooperating with winding. Coils for goblet cores may vary inductance
Depending on the change in the gap. Here we try to change the gap, eg by
inserting a thin plastic film or thin paper, because in this way you can
match the required inductance. Also too strong compression screw core
mounting changes inductance, not to mention that the mere fact of its
inclusion in the hole it can have a big impact. author used screws M2, 5
brass, which caused only the minimum detuning coils, as opposed to steel.

Commissioning of the system is dependent on the possession measurement
capability. Now you will be given simple methods with minimal feature:
when elements are already soldered to the plate, you need a voltmeter
Check the DC voltages the electrodes of transistors, as it may be that
the significant rozrzutach gain transistors - you need to adjust
resistor values ​​in the database. It is best to run after mounting
electronic part assembling the selected housing plate metal or made ​​by
hand. The the simplest case, the cover may be two pieces of bent
aluminum sheet in the shape of a flattened U. On the front panel should
be installed potentiometers P1 and P2 and Pz switch, and a jack socket
for connecting a set of słuchawkowo-mic. It is to provide the front wall
in the scale email. In this case, it may be any digit frequency meter,
even working only to 4MHz. The rear wall should include a power outlet
and antenna. Also, the back of the can BD135 transistor bolted, but by
Mica washer, if the collector is uncovered.

Running is best to start VFO, or by checking the voltage at the emitter
T5, which should be about 4V and the emitter of T6, which may be in the
range of 200-500mV. When setting Pz receiving position, the voltage at
the collector T4, T9 and T8 should be close to half power supply, or up
to about 6V, identically broadcasting with the T3 and T10. also around
half of the supply voltage should appear on the emitters T7 (on
delivery) and T2 (in broadcasting). Current of the transistor T1 You can
also check by measuring voltage drop across the emitter resistor. The
quiescent voltage across the resistor T1 may be in the range 15-25mV.
Its value is affected by light D1 and a resistor R2 (can, if necessary,
change their values). Another necessary step is to check VFO with a
multimeter frequency or extra receiver
for 80m close to the output of the system.

The author in his prototype model, although Designed primarily for
experiments, used a hand-constructed microprocessor digital scale
AVT-5112, connected T6 to the collector via a capacitor 3.9 pF, and the
previous connection to the emitter of the larger capacity resulted in
slight interference to. Such a scale is a very useful equipment Not only
this transceiver. You should know that too retuning a wide range of
generator can be limited by additional resistors connected to extreme
terminal potentiometer. The correct VFO is provided additional capacitor
C20 and the beginning of this can be a trimmer a 30-50pF. If the
generator is running in its own sphere, and the coils were checked eg by
GDO (TDO), then you connect the antenna headphones you can pick up local
stations operating slightly above the 3.7 MHz.

Checking the receiver and its refinement best done using a generator
RF with adjustable output level signal, but the reception quality
correction should be made during good propagation played in the
competition, because then you will definitely hear a lot of stations and
you will be able to improve the system. certainly You can then test the
silencer P2 and improve the sensitivity of the correction values
capacitor C9. You can also choose frequency response of a low-frequency
circuit by adjusting the values ​​of capacitors LF amplifier For
example, in a You can easily narrow band track LF by a small increase in
capacity C33 or C35, and by attaching the resistors R21 and R23
additional capacitors with selected values ​​in the range 330pF ... 1nF.
Such negative feedback Feedback will also to some extent bandwidth
limitation of the top.

Also noticeable improvement in reception, including the partial
elimination of the distortion-band, it can bring to join a capacitor
with a value selected from the range 22nF 10nF ... to the coil L7 -
foundation parallel resonant circuit enhancer attenuation above 3kHz. So
let's experiment to adjust the audio to your liking. The output of the
transmitter, and attached Pz the broadcast, you can check through
additional receiver close the antenna output resistor loaded 50Ω/1W and
oscilloscope, or diode probe. In the simplest case, it may to be a light
bulb 6V bike / 0.6 W, which, thanks zaświecaniu modulation in time will
ensure that most transmitter amplifier is working properly.

One of the necessary steps for run the transmitter is to balance
modulator through the sliders potentiometers P3 and P4, the output pins
the lowest level of the carrier. to this action is best to use a
receiver outside, although the setting with RF probe the smallest signal
level RF will be correct. It should be noted that the diodes modulator
does not necessarily have to be matched quartet, but they must be of the
same series. It is worth more to choose such a close parameters, such as
using a multimeter by measuring the voltage drop across the junction. on
switching to an external receiver web USB side can try to choose
elements mentioned above shifters RF phase and LF for as little unwanted
signal level of the web, but This activity requires a lot of
experimentation and experience. In order to change sideband In our
system, you must cross to bring phase shift signals.

In Figure 4 is shown a sketch sheet Minitransceiver bandwidth. It can
easily be seen on the shifter LF phase gives a phase shift equal to Only
90 ° at a frequency of about 700Hz and 1.5 kHz, as at points A and B
attenuation the second web is about 30dB (better characteristics can be
achieved in a method on filter with a simple filter frequency). Despite
the above mentioned drawbacks and low-power transmitter with a good an
antenna (for example, the dipole 2 x 19.5 m) may be - with good
propagation conditions - make in this minitransceiverze not TinySSB only
home communications 80m band. More experienced engineers author
encourages the modernization of equipment, for example, by replacing the
diode modulator team keys on a digital system (74HC4066, 74HC4053 ...)
and amplifiers popular transistor amplifiers operating with the
formation of characteristic Mw, and share all comments on the operation.

Andrew Janeczek
sp5aht@swiatradio.com.pl

selected parts list translation:

L1 2x18 turns on T37 0.4 DNE-2 (perhaps T37-2?)
(about 5.3 μH)
L2 36 turns on T37 0.4 (perhaps T37-2?)
L3 10 turns on L2 DNE 0.4
L4 26 turns DNE 0.4 on T37-2 (2.8 uh)
L5 3 x 10 turns DNE 0.4 on FT37-43
L6 2 x 400 turns DNE 0.1 on F1001 (Al=400) approx. 250 mh
L7 500 turns DNE 0.1 on F1001 (Al=400) approx. 100 mh

*********** end of excerpt of translation

8985 2013-08-19 09:15:43 vk4ebp Re: Article translation (was: Video of simple SSB phasing receiver)
Hi All,
I speak fluent Polish.... I will try to clean up the Google translati
8986 2013-08-19 09:17:18 jor Re: Article translation (was: Video of simple SSB phasing receiver)
Hi all,

PA2OHH use the phase methode also for his CW QRP transceiver.

Look at http://www.qsl.net/pa2ohh/98txrx.htm

73'Joris PE1KTH

-------------------------