"Gud Ol' Daze", LOL!
Hmmmm,
Funny, I never HAD a
problem with my E.F. Johnson
Messenger One. It was a tube rig that I could use as
base or
mobile. It had a pi-network, so it was easy to
peak then just back off a bit to get maximum performance.
The
main thing in getting it to work properly is to make sure that the coax (Belden 9913 - double shielded 50 ohm) is used and the antenna is
matched to the coax and rig. This is accomplished by sliding the
'stinger' in & out OR using a
tuning box, mounted at the antenna base and chassis grounded. Your library or maybe an old, local, ham friend just might have an old ARRL Handbook showing such a circuit.
A LOT of CB'ers back in the mid-60's used a
jumper across the 3900 ohm resistor in the Final. You got 15 watts of RF, but still only had 3.5 watts of modulation. This made you sound like you were in a
barrel :evil:
Not wanting mine to sound like that, I put a .33 mfd cap at 600wvdc in parallel with the 3900 ohm resistor and got better audio out, which made that Heising modulation
sound more powerful. :wink: :twisted:
I still have two of them, both 120 vac units. One is still on CB, the other has been converted to a 10 meter AM rig, with all the proper modifications: rectifier tube replaced by a diode voltage doubler, filter caps upgraded to higher voltage requirements, 3900 ohm resistor removed and 390 ohm inserted/.33 mfd mylar cap at 1,000wvdc. The voltage doubler increases the B+ from 325 volts to 550 volts and the lowered screen resistor plus cap gives me an output of about 35 watts AM. That's ALL I need for 10 AM, when the band is "open", LOL!
Respectfully,
73,
Don/KA5LQJ
(8Q3224 in 1962)
