[Amps] 30L1 keying

[Jim Thomson]

Date: Tue, 27 Dec 2016 22:43:34 -0600
From: "David Harmon" <k6xyz at sbcglobal.net>
To: "'David Gow'" <d.gow at frontier.com>, <ka9egw at ka9egw.com>,
<amps at contesting.com>
Subject: Re: [Amps] 30L1 keying

The ARB -704 works well on my 3KA and 3K Classic X MKll as well...no
problems.
But....don't use the 704 on a Collins 30L-1 with that -160vdc on the
keyline.
Ameritron claims that the 704 will work with the 30L-1 but they don't say
for how long.
My experience keying the 30L-1 has not been good with this unit....it WILL
fail after a period of time.
I have gone back to the original hard ground keying.


73

David Harmon
K6XYZ

####  I use a opto-22 brand  Opto isolator.    Model ODC-15A. 
4 kv isolation between  input and output side.  Aprx  9-18 vdc
on the input side..at just a few ma.  You can activate the input side
by either sinking...or sourcing. IE: apply a grnd.... or apply 9-18 vdc.
Output side is rated at 200 vdc  at 1 A CCS.  

##  They also make a ODC-15..... which is rated at 60 vdc at 3 A CCS.

##  You can also get them with several different  input voltages, like 5 vdc,
24 vdc  etc.   Built in back emf protection on the output side. 

##  I use them to activate 4  X sped up vac relays, which use 135 vdc in a
RC hotshot speed up circuit. 

##  also use em between yaesu 1000D /  MK-V  and the drake amps.  Drake
amps were modified by removing the oem + 27 vdc  half wave rectifier..and 
replacing with a FWD.  New vdc is now + 63 vdc.   Then the oem spst mech relay
in the yaesus are no longer used to key any of the amps.   The SS output of the
yaesu is instead used... which will  easily key the input of the opto isolator. 

##  These opto isolators are available anywhere, like mouser etc, and made by 
several different companies, like opt-22, crydom,  and also P+B  etc.  

##  easy to either incorporate inside an existing amplifier, or use eternally.  If used
externally, several of then can be used, if  several amps in the shack. 

##  They are lightning fast of course... and 100 %  reliable.   Its one more option.

Jim   VE7RF