EMRFD Message Archive 14453
Message Date From Subject 14453 2017-11-28 07:25:36 nm0s_qrp Announcing - the FDIM2018 2N2222 POWER CHALLENGE!
Announcing - the FDIM2018 2N2222 POWER CHALLENGE!
We QRP enthusiasts have developed a great reputation for doing more with less. Whether that is trying to break a record for mile per watt in a QSO, or designing a transceiver with fewest components, the design skills of our colleagues is undisputable. QRPARCI is presenting our community with the an opportunity to show off these QRP design skills with the FDIM2018 2N2222 POWER CHALLENGE! The challenge is simple: Design and demonstrate a crystal-controlled 40M PA to make the highest sustained power for a period of one minute using only two 2N2222 transistors. This event will take place during Friday, May 18 during FDIM, and the winner recognized at the QRPARCI Banquet on Saturday, May 19.
The rules for the competition are simple, but we have to list every nit-picky detail to test your endurance anyway:
The design is to utilize two, 2N2222 or 2N2222A transistors as the only active circuit elements. There are no limits on the number of diodes, inductors, resistors, capacitors, or transformers, but no other transistors, tubes, or ICs may be used.
The PA must be crystal controlled within the 40M amateur band. Builders are encouraged to use their own crystals, though there will be 7030 kHz HC-49 crystals available at the competition. No external frequency source may be used.
The circuit must fit inside a 12” x 12” x 12” volume. During the power test, the judges will cover the circuit with a blast shield to protect judges and contestants from flying bits!
All circuit components are to be visible for inspection.
A schematic of the circuit is to be provided with each entry
The options for PA cooling are fairly open, but there are restrictions for safety’s sake: No cooling media may be used that are flammable or could emit harmful vapors when heated. No closed loop liquid cooling systems may be used. The entire cooling system must be contained within the 12”x12”x12” volume
There is no requirement for harmonic purity of the output signal, but consider that these designs might be published in QQ, so don't get stupid. A 40M harmonic filter will be included as part of the test equipment to prevent harmonic current from affecting power measurement.
A zero-to-24v variable power supply, dummy load and power meter will be supplied by the judges.
The competition will have two rounds of trials to demonstrate power output of each circuit, with the best performance of each circuit being its final score.
During each test, the builder will connect his circuit, set the power supply voltage and then announce to the judges when to begin measurement. During a period of one minute in which the builder may not touch the circuit or power supply, the minimum power output registered during the test will be the score for that trial. Failure of the circuit in that one minute test period results in a score of ZERO for that round!
If the circuit fails during the first test period, the builder will have five minutes in which to repair it before the second round trials. A solder station, simple hand tools and a supply of 2N2222As will be available.
If your entry sets off the smoke detector in the Holiday Inn, you will be disqualified and may be subjected to rude laughter and finger pointing during the rest of FDIM!
The winner of the FDIM2018 2N2222A POWER CHALLENGE! will be recognized at the QRPARCI Banquet Saturday May 19, 2018, and a PRIZE awarded!
Questions regarding the POWER CHALLENGE may be addressed to David Cripe NM0S, firstname.lastname@example.org. Good luck and good building!
73 Dave NM0S
14455 2017-11-29 10:33:04 Dale Ward Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! What is the reason for excluding closed loop liquid cooling? The technique is well established, safe, reliable and, with proper design, cheaper than heat pipes or massive heat sinks. It almost reads as "old school cooling only" which, if true, is the very antithesis of what hams have always done, I.e. Push the physical and mathematical limits of designs to the limit. Are we as hams that determined to exclude new young people with new techniques from our 'traditional' approach to designs? When the R1/R2 designs first came out they were bleeding edge, innovative and exciting because they employed old designs adapted to newer, cheaper components that performed exceptionally well. The innovation and creativity were applauded and expanded upon with stunning results. No one lamented the lack of tubes in these designs even though tubes were used in the original conceptual designs decades earlier. It was progress, it was what hams do, push the limits of electronic communications. Are we resigned to watching our hobby disappear into a historical footnote simply because we want to hang on to old school techniques to the exclusion of modern, innovative and very effective modern techniques that new, young hams would otherwise embrace? There can be no life without change. I am not young but I do embrace the reality of change being an absolute necessity for growth. In other words we, as individuals, do not HAVE to change but as hams we MUST allow for change or else we are denying the very roots of our own history. 14456 2017-11-29 11:39:23 jgaffke Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! I'm not terribly familiar with this stuff, but perhaps the organizers have safety issues in mind:Especially if they can't know for sure what the cooling medium is.A dewar of liquid nitrogen at -196 C (-321 F) would be fun and fairly easy to obtain.Maybe even effective if you could somehow avoid fracturing the silicon die.Though liquid helium should be banned, a limited resource not to be wasted frivolously.Jerry, KE7ER 14457 2017-11-30 06:44:00 nm0s_qrp Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! The reason for these restrictions is safety, no more or less. We want to avoid exploding boilers, or igniting paraffin vapor, or toxic fluorocarbon gases, or deal with mercury spills, There are plenty of other ways to keep a small transistor cool, and no shortage of creativity to discover new ones. The nature of engineering is the creation of innovative solutions given a particular set of constraints. The constraints of this contest are not intended to exclude innovation or use of effective techniques, but to encourage development of unconventional solutions - for which the QRP community is famous!. Good luck!73 Dave Cripe NM0S 14458 2017-12-01 19:15:04 Leinweber, Glen Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! Dave,
Can you give more details about the Holiday Inn smoke detector?
Might as well try for the booby-prize ;-)
I take it 2N2222 & 2N2222A are TO-18 (metal can). Have launched
a few into ceiling tiles - a new perspective on miles-per-watt.
At my QTH, smoke alarm mostly announces "Dinner's ready!".
14459 2017-12-02 10:02:09 Paul Wilson Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE!
The thought that occurred to me was include a reasonably large Tantalum cap and relays or FETs so it runs okay for say 50 seconds and then the logic reverses the bias on the Tantalum. Instant flames.
73 Paul VA6PW
14461 2017-12-08 22:37:10 iq_rx Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! Hi Dave,Sounds like a great set of rules and a fun competition. I'm tied up this year during FDIM or I'd be tempted to enter an "open loop water cooled" PA. I've done several of those, and they are at the very least conversation pieces. I may try some experiments anyway...Best Regards,Rick KK7B 14462 2017-12-09 00:04:48 w7zoi Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! Rick,Just remember the rule: It's not a transmitter until you have used it to make a contact.73, Wesw7zoi 14463 2017-12-09 20:21:23 AncelB Re: Announcing - the FDIM2018 2N2222 POWER CHALLENGE! Ok guys just ramp up the power and use freeze spray to make ur contact
...also get the metal can trannies.