Just finished building my BitX40 after playing with the circuit for a few weeks. Early tests on mine suggested that using the small booster I have and raising the PA voltage from around 14 to 24 did

Yes it has only been reported in two units so far. So it should not be a show stopper for anyone. The radio is usable and I will simply add an audio low pass filter if need be. For a radio aimed at

Read this old post, you should be able to follow along with your vom: https://groups.io/g/BITX20/message/40808

11.5v should be fine, make sure it is still 11.5 when PTT is pressed. Quiescent IRF510 drain current changing somewhat as they get warm is normal The drop from 6w to 4w when V+ to the IRF510's is

Craig, Just to eliminate audio vibration feedback (microphonics), disconnect an internal speaker and try and external one a short distance away from the circuit board and mic. 73 Mike KF6KXG

If using an external speaker, make sure it has a stereo plug (not a mono one). I mistakenly plugged a mono plug external speaker in and it squealed.

ok here is the entire problem. When I press PPT hear click from relay.don't know which one. receive stops and TX comes up on screen. when I release PPT it goes back into recevive. My watt/swr meter

hello ok when I push PPT the rec will drop out and TX will show up on screen. I hear a relay clicking when I release the PPT it will go back in rec. I can't tell which relay is clicking.MY watt/swr

This is only for uBITX owners in the US right now as I don't want to get into the hassle of International shipping of repaired equipment as I am not sure how foreign customs handles repaired stuff

If you look at the schematic you can see that D7 is directly across the windings of relay K1. The cathode end is connected directly to +12V. The other end is connected to the collector of Q15. If

HI Group. I have been searching and reading topics with regards to using the RD16HHF1 in the uBITX. So far I have only been able to find suggesstions, but no actual implementations... I was testing

Jerry is right. This is a rather rare effect involving only a few nanos. The use of a ceramic resonator would surely contribute to the problem. The best solution is to replace the nano (maybe with a

so looks like this afternoon was a bust, is there anybody going to stick around tonight 7pm / 0000Z ? There is a pile of AM broadcasters coming in up here tonight, playing around under 200 right now.

PA1FOX has done this, but I don't think he has posted detailed results yet. (He has promised to do so). I have some, but have not gotten around to finding out what they do. It looks very good,

I am still waiting for mine. Second order, last oder sat for over a week until I asked about them and was told they were out of stock... So much for customer service. Marco - KG5PRT

the Parts Place is a good place to get some. But they are now on back-order. Also, it is noted that the prices have increased (~$US5.00 for RD16HHF1). It looks like the market is catching up with

That is where I placed my second order. The other place was closer and I should have had them in a couple of days... oh well. Marco - KG5PRT

Arv, I am glad you went to the trouble to post this. I have been puzzling how to do this myself because the switch connection did not make sense to me. Your sketches reflect the way I thought I should

Bill Glad my own uBITX work could be of value to someone else. Arv _-_ Sent from my Verizon, Samsung Galaxy smartphone

Genuine Nano with Quartz Crystals. Replacing the Nano to remedy high frequency audio tone. The official Arduino site says they are out of stock, however I found that the RobotDyn Nano ATmega328