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Rather than cutting the trace as the original instructions said to do, Cutting traces is "hokey", and if it can be avoided, .... I think the original idea behind the "S" kit was a bad design, the Transmit Mixer don't care what you throw at it, so long as it's close to 27 MHz, it's happy...

He's talking about breadboarding the oscillator from the "120" or the "240" kit, making it diode switched on the crystal.

www.amazon.com/gp/product/B094ZCRXMN/ I have 2 of these, one at my house, and one at my shop.

Headphone jack in the front bad contacts? Or Speaker 1 speaker 2 speaker 1+2 switch? The fact that you have RX audio in PA mode, eliminated my first though that TR19 was bad.

Honest oops. Pobody's Nerfect!

Page 2 - TX Freq - Channel 19 is 27.1850 not 27.3850 (Ch38). Otherwise, good!

This works for C29's too, different part numbers, though.

According to https://fcc.report/company/Cobra-Electronics-Corp The first post in this thread with the 29 VCO daughter card (Beken BK4802, like the FM models) is the latest Cobra 29 LXA version submitted with the FCC on 2022-10-27. This version is the one submitted to the FCC 2021-03-02. It...

https://www.worldwidedx.com/threads/new-cobra-29-am-fm.265620/ https://www.worldwidedx.com/threads/cobra-29-ltd-classic-chrome-fm-radios-are-here.266050/ https://www.worldwidedx.com/threads/any-mods-for-the-new-cobra-29-classic-am-fm-yet.266250/...

The FM transmit audio is going into the BK4802 chip, which is actually an FM 2 way transceiver chip, in this case, only being used in the TX mode, for the Cobra 29 FM radios TX (direct frequency) and RX (offset by +10.695, High Side injection into the 1st mixer). The RX functions of the chip...

I am working on designing a replacement CPU board that talks directly to the BK4802 chip they used for this series of radios. I found the "secret sauce" code to translate frequency to PLL codes, and am working on the code to read the Delta Tune pot (which does go to the original CPU board), to...

That is the difference between DC Gain (resistor) and AC Gain (added capacitor) of a circuit. This increases the gain of the circuit for AC amplification.

Take the 3.3k you pulled, solder a wire to extend it, I didn't know if you had a 3.3k laying around or in a drawer, or loose. Now try. You can always rebend it back in shape to restore it later.

----------------------------------------------------------------------------------------- TR16 - E is the Left pin, C is Center pin, B is the Right. B should be about 0.6v to 0.7v above E voltage. Red trace is from the LD pin (15), to JP2 under the PLL IC, then continues towards the back...

What voltages are you getting on TR16 when in TX ? The only thing that "could" pull down Pin7 of IC3 to 2v (also only active in TX) while the LD is a high condition (4.7v??) , could be a shorted Base on TR16. The Emitter should be under a volt, the Base should be .7v above Emitter voltage...

PLL is out of lock. Pin15 of the PLL, if it is High, enables the TX Mixer (IC3) through D14, and the bias for the TX Buffer amp transistor through R62, I sometimes call this the Pre-Driver. If Pin15 is low, this disables (pulls down the voltage) of both of the above.

egg roll too!

Yes, first come, first served. Like I said, "if you still have it then ..."

I'll take it Saturday if you still have it then.

It happens. The link I provided is the same item number you just posted.