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Looks like Hotel Zulu is in Australia so he my find it too expensive to post overseas. Pity he edited the post out.

Agreed, 100%. Definitely was a step in the right direction. I would not be surprised and I think that's a great theory because when I first got this radio it had a lot of surface rust and the bottom stand was removed and it looked like it had been bolted under a shelf (top cover had extra...

Turns out I did not hear it at all on supposed frequency and what I could hear was actual bleed though my laptop speakers nearby. Sorry for the bum steer. Putting headphones on for the ts440s receive today, I found its doing similar to before, in that a 27.405 LSB transmission is actually...

Unfortunately I think I spoke too soon. Today I've been testing with second radio. The second radio was really hard to hear - very low in static/signal on the ts440 regardless of RF Gain position or if I had a screwdriver in antenna socket. At the same time it was blowing the doors off my...

Well Brandon , I think its working!!! Looks like that may been the RX problem. I will verify tomorrow with a second radio and report back. I just installed the new PLL into IC1 (mn6147c from aliexpress) and the 3khz sweep thingy is gone on startup and it has proper volume and no weird noises...

Thanks, Just trying to scrounge up the resistors to try that with what I have on hand. Today I ordered the replacement chip (mn6147c) so in a weeks time I'll put that in.

Reading open with no resistance to ground no matter what ohms range I try. I'm always willing to give it a try! Are you saying tap a voltage source from the radio and bias to supply 2v with a resistor and then supply that to pin 16? Getting excited - I feel like there may be a chance of...

I understand the rules and wish to enter the contest.

Thanks Brandon, I am just slow with it. Re: VCO 4 (radio on 27mhz rx) If I probe D3 it changes audio and drops the TP1 voltage down a bit (7.8v to 7.6v) . TP slowly rises on startup to nearly 7.8v after 5 minutes and sits there pegged out. I just decided to check all voltages as shown in...

Thanks Brandon, I was online when you posted and then the dots problem came back with a vengeance so I couldn't check it. Messed around with it and soldered back an earth strap from a metal trimmer can on PLL Board that had fell off earlier this week and back to usual state (the 3khz sweep...

Think this poxy cheap fm radio worked a treat! Just as you replied I was uploading my video test. I think its oscillating: yeah google AI told me this morning my scope would struggle to pick it up.

Hey Brandon, No dramas on what your saying - all good. Could my 10mhz max oscilloscope see a 9mhz harmonic? I do have analogue fm radios kicking around - I'll round them up and see if any detect it.

Hi Brandon, Sorry to disappear a while ago, I've been really busy on everything but radios - I run a beef cattle farm by myself and sometimes get caught up with big workloads. Fast forward to today, I got a chance to try and sniff the 9mhz harmonic on Q21 (for 36mhz oscillator) as we were...

Good tip Nomad - I will do that in the future.

What about the checking the final bias to see if its in ballpark ~50ma. Might point to an issue in the bias circuit.

I dont have a baofeng (good idea though),108mhz is top of fm broadcast band - could i use a digital fm broadcast receiver?. Also my ts430s has full working receive, so I could use thats to sniff 9mhz using diy H-field probe. I will try that.

I dont know cause my second hand frequency counter needs repair! I dont think I have another receiver that could sniff that 36mhz range either. Only random idea is to try use my laptops tv tuner card maybe as a hack...

Thanks Brandon. Just starting doing voltage probes vs schematic voltages on the 'pink' oscillator chain you described as well as IC13. They all look pretty spot on other than Q21 emitter is 4v where it should be 3.4v. Q21 tested OK

I'll focus on your diagram and just try to process stuff before I repost.

Thanks Brandon, I didn't realize you were on when I deleted that video showing static on key up but after I posted the video I suddenly had full clear audio being received 95-100khz high on ts440s. ie transmit on navaho cb on 27.405AM, received on ts440 at 27.500AM onwards for 500khz.. Basically...