Jeremy,
From those resistance readings, I would say you are OK.
If you have all except Q7 and Q8 installed, do a TUNE and re-check the
voltage on the base solder pads of Q7 or Q8. If you do not see a
voltage between 6.2 and 6.4 volts, replace Q11 and Q13 and retest before
you install Q7 and Q8. You don't want to destroy new PA transistors
with too much base voltage.
You can make measurements without the heatsink when Q7 and Q8 are
removed, but once Q7 and Q8 are mounted, you must have the heatsink
installed if the PA transistors are expected to last longer than 30 seconds!
73,
Don W3FPR
On 2/14/2014 12:04 PM, JeremyJones wrote:
So after reassembling everything minus Q7/8, resistance from ground to
collector pad for Q7/8 starts at 600k ohm then gradually drops down to 54k
ohm before reseting and spiking back up to 600k and dropping again. I
believe this would be a capacitor charging up and then biasing a transistor?
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