Message	Date	From	Subject
7083	2011-12-21 12:22:38	Chris Trask	KISS Mixer Performance
> > > Make before break means all the switches are off. I'd expect an increase > > in conversion loss from that, but not "noise". What say ye? > > > > Same for both edges. The datasheet says that it should only be 0.5nSec, > but that's for a 50 ohm source and load with a shunt capacitance. This has > a series inductance from the transformer leakage inductance. > > I'm going to do some conversion loss tests tomorrow. > I just finished making conversion loss tests. I was a bit surprised at the results, so I did them a second time, scrutinizing everything to make certain there were no mistakes. Here are the results: RF Freq LO Freq Conversion (MHz) (MHz) Loss (dB) 1.0 8.0 -3.9 2.0 7.0 -3.9 5.0 4.0 -3.9 10.0 1.0 -3.9 15.0 6.0 -3.9 20.0 11.0 -4.0 25.0 16.0 -4.0 30.0 21.0 -4.0 35.0 26.0 -4.0 40.0 31.0 -4.0 45.0 36.0 -4.0 50.0 41.0 -4.0 55.0 46.0 -4.0 59.0 50.0 -4.0 So the conversion loss is pretty good even up to 6m. I also did a quick spot-check of the OIP3 at 50MHz RF and found it to be +29dBm. Chris
7097	2011-12-22 18:27:41	kb1gmx	Re: KISS Mixer Performance

7100	2011-12-22 18:49:02	Chris Trask	Re: KISS Mixer Performance
> > > > > > > > > > Make before break means all the switches are off. I'd expect an increase > > > > in conversion loss from that, but not "noise". What say ye? > > > > > > > > > > Same for both edges. The datasheet says that it should only be > > > 0.5nSec, but that's for a 50 ohm source and load with a shunt capacitance. > > > This has a series inductance from the transformer leakage inductance. > > > > > > I'm going to do some conversion loss tests tomorrow. > > > > > > > I just finished making conversion loss tests. I was a bit surprised at > > the results, so I did them a second time, scrutinizing everything to make > > certain there were no mistakes. Here are the results: > > > > RF Freq LO Freq Conversion > > (MHz) (MHz) Loss (dB) > > > > 1.0 8.0 -3.9 > > 2.0 7.0 -3.9 > > 5.0 4.0 -3.9 > > 10.0 1.0 -3.9 > > 15.0 6.0 -3.9 > > 20.0 11.0 -4.0 > > 25.0 16.0 -4.0 > > 30.0 21.0 -4.0 > > 35.0 26.0 -4.0 > > 40.0 31.0 -4.0 > > 45.0 36.0 -4.0 > > 50.0 41.0 -4.0 > > 55.0 46.0 -4.0 > > 59.0 50.0 -4.0 > > > > So the conversion loss is pretty good even up to 6m. I also did a quick > > spot-check of the OIP3 at 50MHz RF and found it to be +29dBm. > > Color me impressed. With better switches we may see higher frequencies. > Not sure if there are any with better ON resistance, but the timing overlap is of concern. I'm going to get some SPST NO and NC switches (Vishay/Siliconix DG2715 and DG2716) later that will let me play with the timing. > > What was the LO to IF difference? > 9.0 MHz > > How is the noise figure? > Haven't gotten that far yet. Tomorrow I'll test the OIP3, and then I'll finish off the revised version of the paper so everyone can see the results. NF testing will be later on. Chris

>
> >
> > >
> > > > Make before break means all the switches are off. I'd expect an

increase

> > > > in conversion loss from that, but not "noise". What say ye?
> > > >
> > >
> > > Same for both edges. The datasheet says that it should only be
> > > 0.5nSec, but that's for a 50 ohm source and load with a shunt

capacitance.

> > > This has a series inductance from the transformer leakage inductance.
> > >
> > > I'm going to do some conversion loss tests tomorrow.
> > >
> >
> > I just finished making conversion loss tests. I was a bit surprised

> > the results, so I did them a second time, scrutinizing everything to

make

> > certain there were no mistakes. Here are the results:
> >
> > RF Freq LO Freq Conversion
> > (MHz) (MHz) Loss (dB)
> >
> > 1.0 8.0 -3.9
> > 2.0 7.0 -3.9
> > 5.0 4.0 -3.9
> > 10.0 1.0 -3.9
> > 15.0 6.0 -3.9
> > 20.0 11.0 -4.0
> > 25.0 16.0 -4.0
> > 30.0 21.0 -4.0
> > 35.0 26.0 -4.0
> > 40.0 31.0 -4.0
> > 45.0 36.0 -4.0
> > 50.0 41.0 -4.0
> > 55.0 46.0 -4.0
> > 59.0 50.0 -4.0
> >
> > So the conversion loss is pretty good even up to 6m. I also did a

quick

> > spot-check of the OIP3 at 50MHz RF and found it to be +29dBm.
>
> Color me impressed. With better switches we may see higher frequencies.
>

Not sure if there are any with better ON resistance, but the timing
overlap is of concern. I'm going to get some SPST NO and NC switches
(Vishay/Siliconix DG2715 and DG2716) later that will let me play with the
timing.

>
> What was the LO to IF difference?
>

9.0 MHz

>
> How is the noise figure?
>

Haven't gotten that far yet. Tomorrow I'll test the OIP3, and then I'll
finish off the revised version of the paper so everyone can see the results.
NF testing will be later on.

Chris