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After 30 years of no activity, I am still learning CW with a straight key which I shall continue to use for the time being.
I recently completed the building of the 80m of the QCX and it is functioning reasonably well except for a few tweaks such as?possibly adding a few turns to T1 transformer. ? After completing the assembly, I connected 50R dummy load, headphones, and straight key (Kent) with mono jack and was ready for alignment. When I powered up with a LiFe battery (9.5V) I was rewarded with a loud tone in headphones and after some agonising?time I established that the transmitter was in fact being keyed (measured power at RF BNC output with DVM)?even though I was not keying. Removal of key jack stopped the keying and I was able to proceed with the alignment. I also have a Palm Radio PPK straight key which has a stereo jack but this also caused the transmitter to turn on without keying and I removed this. The microswitch keyed the transmitter normally as did shorting the two offboard connections at the front of the PCB. My first thought was that there was a fault with the key stereo socket but on closer inspection of this and the circuit diagram it seem that the transmitter is keyed when the either a mono jack or a "standard stereo jack" is inserted in the socket causing a connecting between the ground and either (or both of the contacts in the socket). In fact partially inserting either jack into the socket did not key the transmitter until I started using the key. This is obviously unsatisfactory and I wonder whether there is a "suitable" jack which should be used (unfortunately, and embarrassingly so, I am not yet?up to speed with Iambic keys etc). In fact, I have a short?extension lead with tip, 2 intermediate sections plus the bore which did not set off the transmitter when inserted.Apart from using the microswitch, obviously a quick fix would be to connect a suitable mono (?)?socket to the front 2 key pins?on the PCB?but this is?also not an ideal as the wires could easily break. Have I made a basic mistake or is this to be expected ? If it is to be expected, then I believe a caution is required in the assembly manual stating that "..mono jacks (and simple stereo jacks??)?cannot be used in the key socket or should be of a specific length otherwise the transmitter will be keyed". This would be extremely useful for the inexperienced operator to make it "idiot proof". I have had a lot of pleasure building this kit so please allow this old man a little indulgence as I can't wait to order the 17m version (I have a MTR-3B for 20/30/40m). Comments are invited. Best 73s Robin G4DNP |
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I added a mono jack on mine or you can use a stereo to mono adapter to use a straight key or external keyer. A mono plug inserted creates a short. ? I recently built a 1-watter QRP kit that uses a "smart jack" - it automatically places the keyer in straight key mode when a mono plug is inserted. Something like that would be nice with the QCX. ? |
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Hi? Yes, I can add that to the next firmware version - to only key in straight mode using the tip connection; then if a mono plug shorts the ring to ground, it would not cause a problem. I can add this as a configuration so it can be enabled/disabled.? It appears Robin, you are also saying a stereo plug doesn't work? This should not be the case - the connectors are for 3.5mm stereo plugs! 73 Hans G0UPL ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? On Thu, Dec 7, 2017 at 2:04 AM, <nickpullen@...> wrote: Actually, I am thinking this can be resolved in firmware: |
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Still on the list, Jack, yes... 73 Hans G0UPL On Thu, Jan 18, 2018 at 4:28 PM, Kelly Jack <kellyjack1968@...> wrote: Hans, |
Nick VK4PP