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W1 is the low power adjustment on the Lincoln II without the + Not sure if they are the same. There is a sharp copy of the service manual for the Lincoln II at Simon the Wizard.

Much of the charm of this place is the @nomadradio radio and amplifier sagas. Keep doing what you're doing and never stop being you!

It won't ever tune right if it's close to the ground, especially if you have it mounted horizontal. your either going to have to get it at least 15 feet off of the ground or mount it so the reflector is flat on the ground with the boom/antenna pointed straight up in the air.

This thread dates back to 1969?!? Whoa!

You can make up for no capacitance hat by making the vertical radiator a couple inches longer. The slightly longer radials shouldn't harm the performance any as it's just there to be a counterpoise for the half wave radiator which is why the designers weren't concerned about not making them 9...

That's not super high but a working Bigstick will usually have a flat match even mounted low. If it seems to have ears even though the SWR is 2:1, the matching cap has probably changed value either from too much power or even just age.

Those antennas either have excellent SWR or a real bad one. Two things cause them to have high SWR, too much power or being dropped. The matching network is just free-floating inside and point-to-point soldered making it very fragile to shock. I had a buddy ruin a brand new one back in the day...

Radio Shack had a half wave base antenna with those dimensions called the "Archer Super Maxim 1/2 wave", part number 21-902.

Well, I guess the OP is done!

The plate output capacitance is also much lower on a tetrode than a triode (of the same plate dissipation ratings) which usually requires more plate/tune capacitance for a given frequency range.

BIC lighter BIC radio

Electron Flow

From negative to positive..

@Summertown great to know that the HG version of the 2SC2312 works as well as their 2SC1969 replacement.

In the 40's-60's they made 4 watt carbon potentiometers but the last manufacturer ceased production in the late 60's. I still saw them new at a couple US-based electronics mail-order places until 1975 with dwindling supplies towards the end. All of the common values that the Johnson and Collins...

@HomerBB is pretty industrious, he's probably experimented and answered his own question already.. :D

It's very rare for a bipolar final to be "bad" yet still have the bias set normally (I think it's only happened to me once in 40+ years), that's why I pointed you towards the tank caps as they change value all the time. (there were a couple a little off) As far as replacements, finding real ones...

If you want to run the finals one at a time you can leave them mounted but disconnect both the base and collector on the transistor you are temporarily bypassing.

You might check C176 (It's hard to read, it's the 68pf closest to the antenna jack in the schematic). That cap hardly ever changes value but anything is possible. Also check the collector load C186, 150pf. Instead if trying a variable cap, replace C183 first and leave C184 out, then add back...

If the bias is adjusting OK for each final, they are probably good. I suspect one of the shunt capacitors in the output tank has changed value. Check the values of C177, C183 and C184