Amps
[Top] [All Lists]

[AMPS] PA Relay Sequencing

To: <amps@contesting.com>
Subject: [AMPS] PA Relay Sequencing
From: measures@vc.net (Rich Measures)
Date: Wed, 28 Jul 1999 17:24:56 -0700


>
>Hi all,
>
>I would like to create the right relay time sequencing into my two holer amp.
>Using for input and output Jennings RJ1A (operating time 8ms, release time
>8ms) and for bias switching SDS-S2 Relay (op 8ms, release 5ms). In to the
>input relay circuit I put a RC string 12R/1W and 100µF/50V. These should give
>me a small delay of abt. >1ms. Is that right, that all modern transceivers
>have a build in delay of about 10ms? Will say, after VOX starting or PTT
>activation h.f. power will come 10ms later. I am interested to know delay
>times for Icom 781, FT-1000D, FT-990, TS-870S and TS-850S.
>Thaks,
>
?  Werner - -  Delaying transceiver output until relays close in the 
amplifier is a problematic thing to accomplish.  An easier solution to 
the problem is to speed-up relay closure in the amplifier, so that the 
contacts close before the fastest radio on the market can begin to 
generate RF.   //   Jennings RJ-1A relays can be made to close in <2mS.  
The fastest radio is c. 5mS.  (FT-1000D).  For a make speed-up circuit, 
see Figure 7 on my Web site.  //  Basically, a make speed-up circuit 
overcomes the coil inductance (in this case, c. 0.3H) sooner with a 
V-limited current source.  .Speed up on break is accomplished by putting 
a resistance in series with the reverse diode across the relay's coil.  
>
-  cheers


Rich...

R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures  


--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


<Prev in Thread] Current Thread [Next in Thread>