That's that's about the only thing that's left course, and it may just be a case of denial that I would bother to check them. Guess I'll get on that. Tnx, Ted

Here's my shot at a quick summary regarding AGC circuits for the Bitx40 and uBitx Opinions may vary. When tuning across the band with a stock radio, you might run across a weak station and turn the

Hi, Yes, that looks like it could be a good choice. Just be certain that the power level at that point, on transmit, is within the limits of the attenuator. Off hand I think it is, but there many

Hi Digger, Often the simplest of things are revealed as complex. As Jerry says, the delays are important. The values used allows the attenuation to smoothly increase and track the signal level

The following observations may be of interest to others having just got round to completing my V5 build. 1) For safety I made use of the SMT reverse polarity protection circuit by KC9ON to simplify

It will do that if one of the yellow or blue wires are not connected forgot which one. Probably the RX line. So maybe that connect is damaged at the Raduino. Joe

Tom, The 4302 or the newer 4312 (which seems hard to find) are the modules I'm thinking of. I think the 4302 was mentioned in ZL1AXG's article. The placement

Nextion shows callsign/ver and all zeros on freq?

Thanks for the tip, John. Thing is that I've tried no fewer than four Nano replacements and two other, known operational Raduino boards. That's the part that makes no sense. Bad outputs or clock

Hello Ted, Sorry about the mishap, but it has happened to quite a few of us before. I would try the Raduino off the main board but connected to a PC for supply via USB. If it is gets stuck at firmware

These may be a little overboard for the purpose but I have one of each of these digitally controlled attenuators that I bought to build up my tool set for making RF measurements. This one had the

It came to pass that, in the process of inserting a 7809 between the Raduino daugterboard and its B+ pin-to-mainboard, that I failed to notice a solder blob shorting out the 7809. I made a 90-degree

There are several ways to do this. ALC is just one way. An easier approach is to do it in software. This needs a software that can control the 'mic volume'. you could set the value differently for

I found another kit and info for the AD8307 http://electronics-diy.com/AD8307_USB_0-500MHz_RF_Power_Meter.php Joe KD2NFC

I like the display on the QRP Guys RF probe. However, the input to the AD8307 is not well protected, and any DC at the probe tip will blow the diodes. Here's a cheaper AD8307 RF probe with what looks

Signal level into the D1,2 mixer can be a bit higher than it is into the D3,4 mixer when transmitting SSB. But not by much. Assume the D3,4 mixer has a signal loss of 6dB, the 45mhz crystal has a

Thanks Jerry, Yes that gives me good reference points. So assuming the clocks #1 and #2 are at the same level, it looks like after this mod the signal at T2 (3,5) could be around 10 to 16dB too

A poorly designed AGC circuit could oscillate exactly as you describe. Whether or not it will oscillate depends on the delays through each element and the gain of each element. Both can vary

Hello Dan, After coffee the two and half neurons left seem to start working together..hihi: in fact you should only need to do the second part of the changes since the switch statement does not care

C97 was bad. Failing under load. PITA!