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After replacing R220, R221, C174: Final and driver not installed. Tests done in TX mode Pre-driver: Base - 1.15v Collector - 11.02v Emitter - 0.93v Driver solder pad: Base - 6.04v Collector - 2.89v Emitter - 0.00v Final solder pad: Base - 0.00v Collector - 2.89v Emitter - 0.00v What you...

Going over the schematic I noticed C175 should be a 680pf, but what's in this one is a 560pf. Would this much of a drop cause the base of the driver pad (without driver installed) to show 5.23v? What should the base voltage of the driver pad be without the driver installed?

Gonna wait to throw this other final and driver in until I hear back from you two guys on the above results with no driver/final in circuit, in transmit mode with pre-driver in circuit.

Wanted to give some input before I throw this good driver and final in here. With the driver and final out of circuit, testing solder pads where driver/final goes in transmit mode with volt meter: Driver Base - 5.23v (kind of high I think) Collector - 2.89v Emitter - 0.00v Final Base - 0.00v...

Back on the 55v... The driver, after removing leads from the board is showing as a PNP transistor, whereas the final after removing leads from the board is showing as an NPN. Using multimeter set to diode mode. Used the parts radio to confirm everything else. Getting 27mhz to the pre-The...

Had to run do an OS conversion on another PC. Now I'm gonna get back started on this radio. Tip: For all those that don't want the Windows 11, or would rather stick with Windows 10 while still retaining updates without paying the ESU fees to keep Windows 10 updated another year, then just...

Yanked out and checked: C165 C158 C160 C166 All test around their given values. Probed collector of pre-driver, driver and final. Pre-driver seems to be amping up and steady, final seems to amp up more and steady but the driver doesn't seem as amped up as the pre-driver or the final and isn't a...

Update: Went ahead and replaced tr45 with a new one. Now: Base - 1.51v Collector - 8.28v Emitter - 0.78v Still nothing on external meter. I do see a stronger signal on the monitor radio (almost full scale). I can barely hear my modulation, but it's crackly and not understandable. Nothing got...

Oh ok, I'm an idiot...lol... Base is 1.29v Collector is 8.29v Emitter is 0.00v That's with TR45 removed.

Got all resistors and disc caps back in. Checked over thoroughly for any shorts/solder balls, all clear. TR45 Solder pads with TR45 removed. Checked in transmit mode. Base - 0.50v Collector - 8.29v Emitter - 2.06v

Ok, be back shortly. Thinking the TR45 may be bad. According to the datasheet, the minimum HFe is 10, typical is 80 and maximum is 300. This tr45 shows as 22, which is well below the typical range, closer to the minimum range. Gonna throw these resistors back in, be back shortly.

Ok so C172 is fine. Do I need to replace these resistors before checking the tr45 pads while it's removed?

Curious thing is, C172 (104j, mica cap, large shiny) suppose to be 0.1uf 50wv but tests as a 92nf. From my understanding 0.1uf is 10nf, not 92nf. Took one out of another radio (parts radio), checked it and it also tests as 95nf. On both my tc1 tester and my capacitor meter. I test them twice...

Ok, got back home... Yanked out R221 and R222. Checked both on the tester and then on the ohm meter. R221 out of circuit tests as 1.50k ohm on the tester and 1.496k ohm on the ohm meter. R222 out of circuit tests as 330 ohm in tester and 329.98 ohm on the ohm meter. All the disc caps I...

My bad, I meant R222 which is a 330 ohm. I replaced R222 previously with a new one, now it looks like heat got to the bottom of R222.

C275 tests as a 11pf Tr45 tests as a good transistor with 22 HFe. R220 still tests as a 4.7 ohm. R330 looks like it got hot on the bottom, coating is wrinkled. Got to run pick up a laptop to upgrade, be back shortly.

Replaced that 4.7k ohm resistor back to a 4.7 ohm. Checked for 27mhz at base of driver and final, present on both and holding steady at 27mhz, but, but the 4.7 ohm resistor immediately started smoking and cooked. Still nothing on meter though.

The transmit mixer shows around the right voltages in transmit. Found C175 shorted. Found C182 shorted. Found R220 was open. After replacing those, then the collector voltage on the driver and final went down to 0.41v, they were the right voltages before I changed the above parts. Checked the...

Oh, I see why the circuit still shows as a short with C182 removed. That cap goes to two coils inside two different IFT's. The other end of those coils go to circuit board ground.

Well... Removed R220, tested in tester shows 465 ohms (same as in circuit). Double checked with two ohm meters, bout the same value of 46? ohms. Replaced it: Then the emitter of the pre-driver went up to 2.21v, base and collector remain unchanged. Still no output, still no voltage on the base...