[Lowfer] Re: 600MRG> Need drawing for RF keying stage...

[Bob Roehrig]

On Mon, 4 Feb 2002, ak0b wrote:

> The problem with relays is they have a useful life measure in times
> activated.   I used them to key a beacon and after about 120,000 times they
> fail.  I had to go to a transistor switch.  When used for keying it does not
> take long to get over 100,000.

Well, first off, my using the relay was a "quickie" method of getting the
beacon on the air and being to legally ID it. At QRSS60, it would take
quite a while to operate it 100,000 times (I should live so long).
The one I am using is a pretty high quality unit, not one of the cheaper
DIP ones. I would suspect the reed types would have a longer life cycle
than the typical spring loaded mechanical types.

But ideally, I agree with you that a keying transistor is ultimately the
way to go, which I will eventually do once I start using a real
transmitter.  It was just a lot easier to simply break the RF line running
between the H-P synthesizer and the HI-FI amp that serves as the
transmitter than try and key either unit.


                    73        Bob Roehrig        K9EUI
                    Aurora University Telecom/IS dept.
                    630-844-4898   broehrig@aurora.edu