restore old radio

[WD8PGN]

I have a set of Drake Twins, 4C model. They have not been plugged in since 1986. I am concerned about electrolytic capacitors drying out and causing all kinds of problems when I try to use them. The local ham radio store says they can bring up the voltage "slowly" and let the capacitors "rebuild themselves". The cost will be a flat $200.
This cost is not counting parts and labor if necessary. I feel like they want me to write a blank check for them. Does anyone have any suggestions or comments??

[WB2WIK]

That's ridiculous.

Why not simply buy a surplus Variac (voltage variable transformer) and do this, yourself?  You wouldn't need a large one, a 5A unit (or higher current rated) would do just fine.  

Readily available new, but also available less expensively used, from Fair Radio Sales (Lima, OH), http://www.fairradio.com

Just wire it up with a plug and a socket, plug in the equipment, and slowly crank up the voltage from "zero" to "full" over a period of a few minutes.

73 de Steve WB2WIK/6

[N1TWY]

$200 "reforming" of the caps:

In a word, ripoff.

You will get the units there, then they will call and tell you all sorts of things are wrong...and then offer to just keep the rigs for "parts"...

Thievery at its worst.

Either get a variac and do the reforming yourself, or just change the PS caps...they are available and aren't horrendously pricey. They're good rigs - either way it's worth the effort.

[W2ZE]

Why not just replace the cap's.You can do it for less than 200 Dollars.Reforming electrolytics may not work, and is very dangerous if the cap fails again.Just replace them and save yourself the trouble.

[KO4NR]

Reforming does work if the caps are not too far gone.
You are correct in the procedure, slowly build the
voltage up to the rated voltage of the capacitor you
are reforming.  As an example for a 500 volt
electrolytic start at 50 volts and let it sit and
reform for 1/2 hour then go up 50 volt increments
stopping for the 30 minute reform interval between
each increase in voltage.  This is conservative but
you never know what shape they may be in.

I would replace them if it were mine to do.  Newark
electronics has 500 vdc electrolyitc capactiors made
by United Chemi-Con.
73,
Bill Smith

[W9GB]

If you need a specific capacitor that is no longer manufactured (in the can/size you need) call or write Frontier for brochure.
--------------------
Frontier Capacitor & Electronics
Everett Hoard, Owner
403 S. McIntosh St.
Box 218
Lehr, ND 58460
Phone: (877) 372-2341; Fax (701) 378-2551

"Our business is selling capacitors." Nichicon brand is our main electrolytic line. All electrolytics are new. We offer substantial stocks of silver mica caps. We also rebuild can type capacitors. We will not rebuild any twist-lock type which is available from any supplier.

[N4UE]

I would replace the old caps. You can do it 2 ways:
 
1, leave the can in place, disconnecting it and wire the new caps. point-to-point. Only you'll know the difference
2, gut the can and place new ones inside.

I usually do #2. However, I have a large lathe and cut the cans open. However, you can do it with a Dremel tool.

The suggestions about the Variac are right on. However, the elect. caps have served their duty. Retire and replace them with new ones.

Ron

N4UE