"pegge" wrote in message
...
Hello!

I have a Hallicrafter-combo, SX-117 + HT-44, with a well-built
powersupply.
After not having activated the TX for say abt 10 years , 2 years
ago I tried a contact on 80, however got a report of very severe hum,
switched off, suspecting the PS-HT-capacitors, took them out,
measured too low resistances, started to ´rejuvenite´ them but not
trusting them anyway bought some new ones, but! roughly
the same voltages and capacitances are contained in a volume
abt 20% of the originals, what happens with heat dissipation,
are modern cap´s really so lowlossy? Can I use them, don´t
want any explosions in my basement!!
What´s the experts verdict!

73 / Per/ sm7aha

Per -

The new capacitors are much smaller -- and allow for "restuffing" older
sized components (when required).
Here are some good web pages to review for replacing capacitors (bookmark
for future reference).

Tim Reese's great article
http://www.nmr.mgh.harvard.edu/~reese/electrolytics/

ABCs of capacitors
http://www.justradios.com/captips.html

Phil Nelson's "Replacing Capacitors in Old Radios"
http://www.antiqueradio.org/recap.htm

Rebuild an Electrolytic (2 photos demos - R390A and AC-4)
http://r-390a.us/filter_capacitors.htm

http://www.wb4hfn.com/DrakeArticles/...Rebuilding.htm

Need an axial? (and only have radials)
http://www.wb4hfn.com/DrakeArticles/...elacements.htm

Worried about looks for a historical restoration (Smithsonian caliber) ?
http://www.earlytelevision.org/capreplace.html

Finding modern HV capacitors for restorations
http://www.justradios.com/capacitors.html