toggle quoted messageShow quoted text
well, got the final verdict on my 7000.....Matt from SAR in Michigan called today, turns out it was NOT the finals NOR the driver board.....apparently a diode that biases the finals went bad, Matt said he never saw that one before.....again, very prompt and courteous service from Matt in SAR Technical in Michigan, he just received my radio Friday, and called me about 10 am this morning !!!!
------ Original Message ------
Sent: 1/20/2021 6:38:08 AM
Subject: Re: [ic7000] low power out on HF
Those are metal shields and
there isn’t any heat sink compound on them. The compound is on the bottom of
the transistors. 7 volts is way too high and nearly zero is way too low. Sounds
like both of them are shot. Base on the amount of damage you are seeing, make
sure the current sensing resistors are good. Usually, a visual inspection is
all you need. Don’t forget to set the bias on each transistor when you replace
On TX, I
get almost 7 volts on 1 final.....less than half a volt on the other.....looks
like that area got very hot at one time....should there be heat sink compound
between the metal plate on top of the finals and the case? The VHF/UHF finals
all have "springs" on them to contact the case, not so on the hf
Original Message ------
1/19/2021 8:26:21 AM
Re: [ic7000] low power out on HF
25 watts kind of indicates one of the PA transistors has failed.
Measure the gate voltage in TX. It should be anywhere between 3.5 and 4.5
volts. It should also be zero in RX.
getting about 25 watts out or so on HF, VHF/UHF is fine, full power.....Its NOT
the power cord, I've tried a couple different ones, same result, and those
cords work fine with my 7300, I had a problem with the 7000 before, actually no
power out on HF and SARS in Michigan, replaced maybe the driver transistor, is
it common for this part to go bad? Any thing to watch out for to prevent it
from happening in the future.