That heatsink is too big for where I like to mount it. Is there enough room for a fan be mounted in place of the speaker?
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Uniden 980 SSB
- Thread starter Mudfoot
- Start date
Yea if your talking about taking the speaker out. There isn't anything sticking up at all. I will say no matter how hot it got it never drifted or lost power I am just a guy that hates heat in a radio so I always go a little overboard
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Just so you know the rivets for the FCC ID plate has holes in them big enough to get like 20 gauge wire through them, that's where I did the fan wiring
I sure hope the Service Manual for this radio is published real soon. It shouldn't get hot like that. Possible that the final or driver bias is off. Either that, or you have long QSO's /keydowns.
I'd keep an eye on it too . . .
Well Robb it's like this, radio got here doing 5 watts, it has a 2 year warranty, if it blows up oh well back it will go I have not modified anything, just turned a few pots to get over 10 watts, I can always turn them back they did not have any kind of sealer or lock tite on them. Right now it does work very well and I like it a lot. At 5 watts they had to be kidding, that and no audio on SSB. It sure works great now.
If it's getting hot, check the voltage at the gate of the final. (I'm going to assume it's a mosfet final.) If it's anything over 4 volts there's a problem. Usually radios with mosfets tend to run hot if there's too much voltage on the gate. About 3.75-3.85 volts is a good number for bias voltage to the gate.
~Cheers~
~Cheers~
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well I have been around a few days, and over the years I did learn to leave the bios alone if it is close. I think one time in the 80's I blew up a final and driver by trying to set the bios too high to get some power. The 4 volt is a good thing to remember for mosfet finals, was not sure what they should be. Thank You
Oh yeah, at this point, you don't want to mess with it, just check it. Since it'll be under warranty, I'd advise against doing any modifications on it like that. It's just a curiosity thing.
~Cheers~
~Cheers~
Man, even the test points for doing alignments are hard to see with the naked eye.
The VR adjustment pots are incredibly small too.
Q203 and the transistor next to looks like they are driving a MOSFET for output power - as a guess.
If so; then the VR at the base of the TO-220 device must be the voltage bias - another guess.
Wonder if those new conductive glues will work for repairing bad joints or even replacing these SMT parts.
There is just no way ones hands can be steady enough to work comfortably in this thing.
Then there is just being able to read the parts and replacing them.
Imagine putting a diode in backwards if it needed one?
Looks like a PLL chip in the lower left corner probably controlled by another chip on the face control board.
Very streamlined; very impressive.
I pity da fool repairman that has to fix these things.
Woof!
These blown-up pictures are messing with my head; I feel like an ant.
The VR adjustment pots are incredibly small too.
Q203 and the transistor next to looks like they are driving a MOSFET for output power - as a guess.
If so; then the VR at the base of the TO-220 device must be the voltage bias - another guess.
Wonder if those new conductive glues will work for repairing bad joints or even replacing these SMT parts.
There is just no way ones hands can be steady enough to work comfortably in this thing.
Then there is just being able to read the parts and replacing them.
Imagine putting a diode in backwards if it needed one?
Looks like a PLL chip in the lower left corner probably controlled by another chip on the face control board.
Very streamlined; very impressive.
I pity da fool repairman that has to fix these things.
Woof!
These blown-up pictures are messing with my head; I feel like an ant.
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You guys asked for high res 
I couldn't even read the values until I zoomed in with camera.
I talked to Dxman tonight and with the turner +3 he said the audio was loud and clear. Stock mike is crap. Throw a power mike on for sure.
I couldn't even read the values until I zoomed in with camera.
I talked to Dxman tonight and with the turner +3 he said the audio was loud and clear. Stock mike is crap. Throw a power mike on for sure.
Mitsubishi rd16hhf1.
Data sheet.
http://www.rfparts.com/pdf_docs/RD/rd16hhf1.pdf
RD16HHF1 is a MOS FET type transistor specifically
designed for HF RF power amplifiers applications.
FEATURES
•High power gain:
Pout>16W, Gp>16dB @Vdd=12.5V,f=30MHz
73
Jeff
Data sheet.
http://www.rfparts.com/pdf_docs/RD/rd16hhf1.pdf
RD16HHF1 is a MOS FET type transistor specifically
designed for HF RF power amplifiers applications.
FEATURES
•High power gain:
Pout>16W, Gp>16dB @Vdd=12.5V,f=30MHz
73
Jeff
Thanks for the high rez pics! Looks like D32 and D33 could be the trick for mods! Maybe!! 
Also the part ID of the final is cool.... shows it to be limited but not too bad.... I wonder if this is a similar final used as in the RL amps?
This 980 reminds me of the TRC-485 to a degree but a generation or two ahead! :blink:
My turn is coming for a new one real soon!
73 mechanic!
Also the part ID of the final is cool.... shows it to be limited but not too bad.... I wonder if this is a similar final used as in the RL amps?
This 980 reminds me of the TRC-485 to a degree but a generation or two ahead! :blink:
My turn is coming for a new one real soon!
73 mechanic!
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