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Front View

I would then download the user and alignment manuals and all the N4PL files plus the 3 flavors of

sprocket repair. The annotated schematics are excellent. Use these in combination with the User

Manual module schematics.

After all this fun, I strongly suggest not attempting to work on this rig unless you have RF circuit lab tech

experience and a pretty robust set of lab equipment with a calibrated VTVM like and HP-410C and a

quality frequency counter. Replacement parts are all pretty “unobtanium” except for NTE replacement

matches, caps and resistors. Buying a parts rig is also highly recommended.

Suggested First Steps

1. Power up for 48 hours with a variac or 100 watt light bulb in series with the AC mains to re-from

old electrolytic capacitors. I have not had to replace any high or low voltage capacitors after this,

fingers crossed.

2. Verify/adjust all AVR board voltages. I adjusted 8.2VDC and 5VDC no problem but my 6VDC

output for was a low 5.3VDC (should be 5.5-6.5VDC and is used solely for VFO. After

considerable research, I discovered that the 2SC372Y transistors are very poor fab/materials

and the 6 volt regulation was horrible resulting in a 50Hz transmit-receive delta. I replaced Q658

with an NTE85 and I now have 6.2VDC with very good regulation. I subsequently changed all

other 2SC372Ys on the AVR board hoping to improve 8.2VDC regulation. This second effort

yielded marginally better improvements.

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Uniden 2020 Informazioni Techniche Pagina 2