Re: Dip Meter TC Tuner

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Ed Phillips by way of Terry Fritz <teslalist-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

Tesla list wrote:
 >
 > Original poster: "S & J Young by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" <youngs-at-konnections-dot-net>

 > I plan to try it.  The only problem is finding variable capacitors.  For the
 > lower frequencies of TCs, variable caps of several hundred pF would be best.
 > Might have to cannibalize one out of a cheap AM radio.  If you know of
 > sources, please post it or email me directly - they are becoming scarce
 > items.
 >
 > Thanks,
 > --Steve Young

	There are plenty of sources for BC type variables, including dual 365
uufd units.  You want AIR variables, not various kinds of trimmers.
Usually a bit pricey at ten or twenty bucks.  There are always ham swap
meets where you can find lots of stuff like that, including cheap units
which have variable capacitors in them.

	Fair Radio Sales (www.fairradio-dot-com/airv.htm) has some pretty good
looking dual variables for $22.00, a pretty good price for the quality.
They also have a FIVE gang 20 to 425 uufd capacitor for $16.00.  Kinda
big but excellent for a VLF "GDO".  Good place to do business, and you
can always give them a phone call.

	C and H Sales often has them in the store,  but not in the catalog.

	Other places to start:

	www.oldradioparts-dot-com

	www.oldradioworld.de	
    (German outfit, has dual 320 uufd "tuning capacitors" for $15.00
    (plus shipping, of course)

	www.oselectronics-dot-com	(Has a good selection at reasonable prices)

	In thinking about it, I suspect you are better off using a relatively
small capacitor (say 300-500 uufd) and a larger inductor for a dip
meter.  You need an inductor with a big enough diameter that it is easy
to couple to the stuff you want to measure.

Ed