Topband: Vacuum relay testing

[by way of Bill Tippett <btippett@alum.mit.edu>]

Date: Sun, 01 Apr 2007 15:20:20 -0700
From: Thomas <ac7a at cox.net>
Subject: Re: Topband: Vacuum relay testing


Gentlemen,

This has been a most interesting discussion regarding my original 
question regarding a circuit which initially energizes a 26.5V relay, 
from a 12V source. The reason I first asked the question is I am 
attempting to keep everything  in my station operational with 12 to 
13.8V. That is because in the case of an emergency I want the station 
to be fully operational with just one low voltage storage battery.

Tom's (W8JI)  thorough analysis of the relay construction and 
operation and Wolf's measurements have convinced me that as long as 
the initial energization requirements have been achieved it is 
completely acceptable to idle back to a holding voltage within the 
relay's specified range. I plan to bench test both the K6XX circuit 
and the other circuit suggested by Kjell - PB3SM/SM6CPI. It was just 
published in the Dutch magazine "Electron." and was developed by PE1MWB.

I would like to thank all on the list who contributed to this 
discussion. Certainly by now I know I am not the only one who has 
contemplated using, and even applied a higher coil voltage relay in a 
lower voltage system. If all goes well my 45-foot, 160/80/40/30M 
vertical will be replaced with a new 65-foot version by next fall.

Best Regards, Thomas - AC7A