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is there anyone who has tried this on one of these yet? i have a 810 and a 465 an not sure on were to strart other than 2x erf2030 1x396fn 1x 396dr ... other than that im stuck so any help is appreciated

Uniden 810e Driver and Final Transistor Replacement

THIS IS UNTESTED i don't have this rig sorry

Required Parts:
2pcs ERF-2030
1pc EN-369DR
1pc EN-369FN
1pc 1000pF ceramic disc capacitor
1pc 33K ohm, 1/2 watt resistor
1pc 470K ohm, 1/2 watt resistor
Heatsink Compound


1 Remove Final
2 Remove Driver
3 Remove L29
4 Remove L32
5 Remove C143
6 Remove C211 NOTE: Is on back of PCB @ finel 470P/UJ
7 Remove C145
8 Remove C202
9 Remove C180

10 Replace both Final and Driver with ERF-2030s. Note: ERF-2030 mounts identically to the Ones you removed

11 Add 33K ohm resistor (1/2 watt) (solder side of PCB) from ERF-2030 gate leg of Final to the end of R170 that is closest to the face of the radio

12 Add 470K ohm resistor (1/2 watt)(solder side of PCB) from ERF-2030 gate leg of Driver to the right leg of VR9 that is closest to the face of the radio

(NOTE: BOTTOM VIEW OF PCB The ERF-2030's Gate is the Right most leg and the Source is the Left most leg)
(Note: insulate the leads of the resistor from the surrounding traces using heat shrink tubing.)



13 Add 1000pF ceramic disc capacitor across C146 (solder side of PCB) NOTE: keep C146 470Pf in place..

14 Install EN-369FN at Final (solder side of PCB). Solder the positive lead (+) to the ERF-2030 gate.
Solder the negative lead (unmarked) to the ERF-2030 source.

15 Install EN-369DR at Driver (solder side of PCB). Solder the positive lead (+) to the ERF-2030 gate.
Solder the negative lead (unmarked) to the ERF-2030 source

be sure to check all work!!! and go over your Schematics and PCB Layout.

I hope this helps 617
I makes no warranties or representations as to its accuracy and assumes no liability or
responsibility for any errors or omissions in the Content of this post TRY AT YOUR OWN RISK!!!!

thank you very much.. i have been studying the schematic and have pretty much half of what you have listed done so i guess i was on the right track..so far.. i will cross over what you have listed and give it a try if all looks as good as you have posted... thanks again and i will post my results for others to use..

Hi, thats a good mode for the 810e, has anyone got info to put mosfet finals in a PC122???, not the XL, cheers Andy

i think i saw something for the trc-465. same as pc-122 i believe. post your findings . thanks

no12nv wrote:thank you very much.. i have been studying the schematic and have pretty much half of what you have listed done so i guess i was on the right track..so far.. i will cross over what you have listed and give it a try if all looks as good as you have posted... thanks again and i will post my results for others to use..

Well it's been 2 years and 5 months or so now but i would like to know how every thing worked out for you no12nv

Thanks 617

Hi 817,

About to do this mod on a PC122, using 520 mosfets, we will see if you are right, and I do think you are,

Cheers Pirate

What other kinds of mods have u found for the royce 640? i just got one and its a sharp looking radio. but cant find much on it but a old flyer that said it cost almost 500 bucks back in the day.