Re: VFO Stability


From: MSgt Cameron C.R. Bailey (CBAILEY@PAMDT.ANG.AF.MIL)
Date: Mon Aug 07 1995 - 14:18:42 EDT

Yes you are correct. We used to use Bathtub Caulk sealants to seal
repacement antennas on aircraft. The Air Force does not approve it for that
use. There are approved sealants known as potting compounds. The ones that
comply with MIL specifications are known commonly as RTV (Room Temperature
Vulcanizing). They are in most cases a two part mixture. Some of the ones
used on aircraft can withstand temparature extremes. Be careful, some
potting compounds are known as reverting potting compounds. They will revert
back to liquid after 2 years to reseal connectors. They can be messy.
There are some encapsulants out there for sealing cable splice cases. Talk
to your telephone/catv friends. I don't know if you can buy small quantities
of it.
I prefer to use the insulating varnish (GLYPT) on coil forms. There are
other special coatings you can use made just for coils called Q-dope. If you
are not concerned with heat, you may consider using sealing wax. It is easy
to remelt. Don't let your circuit in the hot sun though. :^) Chuck would
have problems.

72 de kt3a

Cam Bailey
SOGNET LAN Administrator (Banyan)
211 Engineering Installation Squadron
Fort Indiantown Gap (Annville) PA
DSN: 491-8737 Comm: 717-861-8737 FAX: 8268

Search QRP-L Archives

[ QRP-L Archive | ]
[ 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 ]


This archive was generated by hypermail 2b29 on Fri Jun 02 2000 - 11:28:25 EDT