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[Amps] 10 kw CCS on 6M..using the 3CX-6000A7...Part 7.

Subject: [Amps] 10 kw CCS on 6M..using the 3CX-6000A7...Part 7.
From: "jim.thom" <>
Date: Fri, 21 Oct 2022 21:06:46 -0700
List-post: <>
10 kw CCS on 6M..using the 3CX-6000A7...Part 7.

Here, the bottom of the chassis is completed.

The red thing is the opto isolator.   To turn it on, a ground is applied
from the xcvr.
The 2 x small RF chokes are wired right to the cathode.  They keep drive
RF  from getting back into the rear apron test jacks, where the true-rms
dvm probes are plugged in. Bypass caps installed everywhere.   Resistor in
one leg of the chokes is in case the rear test jacks ever got shorted by
accident....esp with a 80 amp fil xfmr.

Series diodes used for bias. Switch used to switch bias  between  SSB +
FT-8 / CW.

Rear apron FAST  3agc grid fuse wired between negative  terminal of grid
current meter..and chassis.  Suck too much grid current, and grid fuse
opens up.  With no path for DC grid current, amp can't be driven.  PO drops
to zero, and input swr rises to near infinity, and xcr / ipa shuts down
asap, event over.

Paralleled safety diodes wired between B- and chassis.  This keep the B-
 within +/- .7 vdc  of chassis potential at all times.  Resistor between
CT  and chassis in RF deck....and also a 2nd resistor at the other end of
the cable in the  HV supply, (where the fil xfmr is located)... is another
safety device.  If the CT connection  is lost between the RF deck  and HV
supply box, this ensures the CT still has a path between the 2 x box's.
With CT  open, the cathode voltage will soar to almost near B+ levels.  CT
+ grnd  and 240vac all go through the (white)  twist lock receptacle.

The 2 x high powered RJ2B vac relays (with contacts in parallel)  will be
located on top side of chassis, between vac load cap..and the 7-16 DIN
output connector.

Scot spent hrs on this, it's tedious. He's built  a lot of
amplifiers....and power supplies. Only difference here is this is the 1st
time building a high powered 6M amplifier.  He's been sick all this week,
and has > 1/2 dozen linear amps in for repair.
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