>
>Tom says:
>
>>> You can get 500 volt rated ones - I think from Philips. Not common,
>>> though.
>
>I should have said 'not common at your local hobbyist component dealer'
>
>>You can buy 1000 volt and higher rated 1/2 watt and higher power
>>resistors all over the place, including Phillips. They aren't all that
>>rare, as a matter of fact they are quite common.
>
>Can't find suitable values in the catalogue of our usual disty - 1kV and
>above voltage ratings are too many megohms. Probably more common in the US
>
>>I would not depend on Hamfest deals or Surplus Sam's resistors
>>being more than 250 volts RMS, however.
>
>NO WAY!! You might find new stock, boxed, with mfrs part numbers at such
>sources, but as Tom says, you can't rely on them.
>
? For my last amplifier project, I wanted to save space over using block
rectifiers and heatsinks, so I decided to use individual diodes mounted
on G10 perfboard. . Using a HV breakdown tester, I sorted a batch of
1N5408s according to measured avalanche volts/piv. . The actual piv in
the rectifier unit was 8100v per leg with 240vac input and no load. // I
used similar diodes in each leg, a paltry30% safety factor, and no
"equalizers" . The supply delivers approx. 7200vdc on SSB to an 8169.
That was over ten years ago. So far, no problems. // The event that
caused me to consider not using "equalizers" in the anode supply was the
realization that manufacturers had stopped using them.
- cheers, Peter.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|