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Wildcat__444
New member
Username: Wildcat__444
Post Number: 4
Registered: 8-2009
| | Posted on Tuesday, September 29, 2020 - 1:21 pm: | 
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Hi, I am restoring an old Tram D201 (23 ch with PC boards from late 1976) that I picked up, and want to do it right. I have scoured internet forums and sites, posted questions, and found it quite a task to gather what is needed to tackle this, but I am having fun!
RESISTORS & CAPACITORS:
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* As suggested, I will start by replacing all high wattage resistors, and upgrading the 1w to 2, the 2w to 3, the 3w to 4, the 7w to 10, and the 15w (all I could find were two 10w to either put in series or parallel depending on the value used) for a total of 20w.
* I will also start with replacing all electrolytics and the two line filter caps. I am confident in my selection of 50uf and 100uf 500v caps to replace the multi-section caps. I am also confident in my selection of two .0047uF X1Y2 safety caps from line to ground, and a .1uF X2 rated cap across the lines.
But what about the rest of the electrolytic caps... what voltages should the 16v, 150v, 250v, etc. be increased to if any? Should any of the capacitance values be changed? How about the wattage of the hi wattage resistors... is increasing to the next higher wattage enough for all positions?
Thanks!!
Not some average over-modulated, PLL controlled, solid-state weak-watt.
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Tech833
Moderator
Username: Tech833
Post Number: 2471
Registered: 8-2002
| | Posted on Monday, October 05, 2020 - 11:31 pm: |
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Unless the resistors have failed, I would leave them alone. Whoever said to replace all the resistors is clearly a hack.
Replacing all the electrolytic capacitors is sound advice. Electrolytic capacitors have a limited lifespan, even if sitting on a shelf unused. Replace 16 volt caps with anything above that voltage wise that fits the physical profile. Like a 25 volt cap of the same uF value.
Do not start "upgrading" capacitors by choosing larger values thinking it will improve something. You're only asking for trouble unless you understand how the circuit works.
Your radio 'Mythbuster' since 1998
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