RE: [Repeater-Builder] Hi All, Help with Building Cavity

[Randy & Karen Long]

Joe,   My experience was that with silver plating, so long as it was reasonably “thick” (it’s all relative) I have had no problem with summer Vs winter tuning. Problems do arise if the plating is too thin as it tends to peel off inside… detuning the cans and the only short time fix is to knock a rubber mallet on the side of the cans (gently but firmly) causing the platting that has become loose to fall to the bottom and all is well with the world again. With a reasonable plating job, the tuning remains pretty constant is my experience. Perhaps climates that are more humid than we have here in the Colorado area have more of an issue. I dunno J BTW current relative humidity is 14%.   Randy, W0AVV   From: Joe [mailto:[EMAIL PROTECTED] Sent: Thursday, August 05, 2004 6:49 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Hi All, Help with Building Cavity   I had a set of copper copper pipe duplexers for 220 years ago.  I thinnk they were 4 inch in diameter.  I had a stability problem due to temperature changes.  They required a "winter tune" and "summer tune" twice a year.  I used them for several years and the taught me why I neede to find a good set of duplexers.  I learned alot from those cans.   I contemplated the PC board cavities, but heard that they were even more unstable than the copper pipe.   There was some scheme to silver plate the PC boards using DC current, some sort of solution, and silver coins.  The plating was extremely thin, but did work.   73, Joe, K1ike Randy & Karen Long <[EMAIL PROTECTED]> wrote: Ed, I have a set built out of the May 1973 QST... With few modifications they work as well or better than the Wacoms or Cellwaves I have used. Am currently sourcing some 4" type L copper now to build more. If you have mort time than money, you can come up with duplexers that may not always be the prettiest, but darn functional. QST also had an article I am looking back to see if I can find, that if I recall is called the "Six-pack". Its made from double-sided PC boards and then plated with Silver as a part of the construction. I have not talked to anyone who has used them, or even built them, but certainly am looking at them for a repeater that we can back pack to its destination. Randy, W0AVV Yahoo! Groups Links To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/   To unsubscribe from this group, send an email to: [EMAIL PROTECTED]   Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.