[Boatanchors] ARC 5 stuff - LIST

[Meir WF2U]

I also did that kind of things when I was young and stupidly thought that
there is an infinite supply of surplus radios, so modifying/destroying a few
won't matter in the long run. 
I know better now.
The ARC-5 type transmitters if properly matched to the antenna (bear in mind
the output circuit is not designed for a 50 ohm coax-fed resonant antenna,
so additional, external matching is necessary, with the TVI low-pass filter.
Also, keeping the voltages to what the original system is designed for and
using it at the rated power as specified, keep everything under control,
including TVI.
But in those days almost everything, including commercially manufactured ham
transmitters had TVI if further precautions were not taken.
The surplus transmitters' bad reputation as to harmonics, instability  and
TVI spread because hams didn't use the systems as designed, at the supply
voltages and  power levels as specified, loaded them into antennas they were
not designed to work into, thereby causing all the on-the-air problems.
Properly used, with original voltage levels, loading and matching them
properly, makes them no worse than their contemporary ham transmitters.
Many of us still use WW2 surplus equipment on the ham bands, as close as
possible to the original system configuration with original power supplies,
racks, cabling, etc, as the radios were designed and we have no problems at
all.

73, Meir WF2U
Landrum, SC



-----Original Message-----
From: boatanchors-bounces at mailman.qth.net
[mailto:boatanchors-bounces at mailman.qth.net] On Behalf Of Jim Brannigan
Sent: Sunday, September 23, 2007 11:43 AM
To: Meir WF2U; 'RAY FRIESS'; boatanchors at mailman.qth.net
Subject: Re: [Boatanchors] ARC 5 stuff - LIST

I had an ARC-5 on 40CW that caused more TVI key-up than key-down.......
it had most of the parts from the MD-7 modulator on a separate Power 
supply/modulator deck.

Also, I modified one to use as a VFO for a Central Electronics 20A (9Mcs.?)

Jim


> Ray,
>
> I forwarded your list to the ARC-5 mailing list (ARC5 at mailman.qth.net,
> website http://mailman.qth.net/mailman/listinfo/arc5 , where many of us
> still appreciate, collect, restore to original condition and use these 
> nice
> old pieces of history.
> We don't cut them up for parts (except when they're beyond restoration, 
> and
> they become parts donors to restoration candidates), we don't hack them up
> for VFO's and such.
>
> 73, Meir WF2U
> Landrum, SC
>


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