All the AGC circuits proposed in this forum (and there have been many) have a fast attack and then a relatively slow decay. That way when the QRO guy across town keys up, it saves our ears as much

Sounds like you’ve had some bad luck. Order some new parts and just push through it. 73 Joe KD2NFC

HI, An additional, somewhat oversimplified, way to look at the AGC control loop is this: If you consider the transistor (or other type of amplifier in the control part of the loop) provides 180

Joe, After fixing the first Raduino shorting, no luck. Maybe it's done, not sure yet. Somewhere along the line of hooking up a spare, I got pin 3 (Clock #2) and pin 4 (Gnd) a bit close for a while.

Hi, John. I got a Nano generic to load up the diagnostic sketch, attached it to the Raduino (out of the radio), and ran through the control function tests. It saw the i2c bus and the si5351. I ran

Thanks again Jerry. I used to work with electronics decades ago and have forgotten almost all of it. Not in design but with repair and maintenance of telemetry and then audio equipment. The uBITX has

Digger previously wrote: Does the delay in part prevent oscillations by introducing a phase shift? I guess didn't quite answer your question Consider an amp with positive feedback and no delays

Also, and still assuming the symptoms are that at boot up the display stops at the version and call sign being shown, in the Ian Lee's software version the i2c address of the si5351 can be changed for

I have and use several of the 3S and 4S charge controllers. These have between-cell connections for charge balancing. Seems to work well because I have rebuilt a number of old Ni-Cad drills so

Makes sense. Thanks Jerry

Barkhausen stability criterion is dense. If you find an explanation that is sufficient to do design work without being dense, do let us know! There are thousands of 3'rd year undergraduate

I just dumped all the photos I had that I was able to get from him. I put them here: https://groups.io/g/BITX20/album?id=89704&p=Created,,,20,2,0,0 I put other non image files here:

Daniel's three cell lithium ion 18650 holder with protection from fasttech.com looks promising. Unfortunately, from the "discussion" section there, I doubt it does charge balancing across the

Joe, Thanks for responding. Can you point us to Sunil's instructions that state how to hook up his AGC board? I clicked on "Download Manual" on his website, got an archive with a dozen files, but

Thanks Don and Jerry for your explanations. In my OP I wasn't thinking about that what I described were oscillations, and as you wrote the parts are chosen to stabilize the circuit and prevent that.

Hi Ted. You did say that you can’t see frequency on LCD. But does the LCD functions let you still control the radio in some way or another. Like can you switch bands. If so that would suggest you

For powering the radio from batteries look for an "automatic buck-boost" regulator. This type will maintain your desired output V as the battery runs down. A "step down" regulator

Jerry I have had great success in hooking up Sunil’s AGC. I could be the poster child. I even determined a better location to grab audio instead of Vol H which is on the relay side of the R70

Hello Ted, I will leave the recommendations for a new Raduino to others. In the mean time, and as an alternative to the chainsaw (hihi), since you seem to have i2c activity you could, if you want to

You need a 3 cell protected holder, like this one: https://www.fasttech.com/product/1161200-3s1p-18650-11-1v-battery-holder-case-li-ion-pcm