Message 26895 in TECH.WW
From: G8MNY
Date: Wed, 29 Jul 26 16:36:00 Z
Newsgroups: TECH.WW
Subject: Using 2 HF PAs
Message-ID: <595_GB7CIP>
Path: N2MH4|VE3KPG|VE3CGR|LU9DCE|LU4ECL|ED1ZAC|GB7CIP
R:260729/1642Z 34604@N2MH4.#SENC.NC.USA.NOAM LinBPQ6.0.24
R:260729/1641Z 27528@VE3KPG.#ECON.ON.CAN.NOAM BPQ6.0.25
R:260729/1641Z 88915@VE3CGR.#SCON.ON.CAN.NOAM LinBPQ6.0.25
R:260729/1641Z 18732@LU9DCE.TOR.BA.ARG.SOAM LinBPQ6.0.25
R:260729/1640Z @:LU4ECL.LP.BA.ARG.SOAM #:57713 [LA PLATA] FBB7.00e $:595_GB7CIP
R:260729/1640Z @:ED1ZAC.EAC.ESP.EU #:21796 [EANET1G.06] $:595_GB7CIP
R:260729/1636Z @:GB7CIP.#32.GBR.EURO #:595 [Caterham Surrey GBR] $:595_GB7CIP
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW
By G8MNY (New Aug 13)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
At an 8 day Ham Summer Camp I needed to use 1 of 2 HF PAs for /P. One was a
500W Transistor PA floated on a large battery that allowed just a small petrol
650W generator to keep the batteries topped up, and the other was a Valve Amp
used in the colder nights and that needed much bigger generators (2.3 / 7kW).
I looked at the 2 possible connection systems...
FULLY SWITCHED SERIES RF & TEED CONTROL LINES
The switched system is complex, unless relays are used.
The series and teed system assumes PA2 can handle PA1 Tx power in through mode!
Steering diodes my be needed to isolate the powered off PA from affecting PTT &
ALC lines...
Add diodes if there is any affect.
steering diodes were not needed.
Of course NEVER enable both PAs together! However the ALCs will work overtime
if you accidenty do!
See my Tech bul "T500 M 12V 500W HF Linear", "PTT line for Drake L-4B PA", &
"ALC line for Drake L-4B PA".
Why Don't U send an interesting bul?
73 De John, G8MNY @ GB7CIP
← Return to Bulletin List