[Boatanchors] ARC 5 stuff - LIST

[Jim Brannigan]

No Meir, they were not wasted.

The Surplus radios of the 40's, 50's, 60's and even into the 70's provided a 
boon to the radio hobby and the advancement of the electronic arts.
This enormous supply of cheap electronics was cut up for parts, modified 
into early SSB transmitters and performance receivers (Q-5ers),
used to explore the VHF and UHF bands and some used as-is.
This cheap and plentiful source made it possible for many to become 
electronics hobbyists and start electronic careers.
More than a few electronics firms were launched using cheap surplus 
components.

It is nice that a few are preserved in their original state, but it would 
have been a shame if the prevailing wisdom was to preserve all of them,
then the state of electronic development would have been frozen at VJ Day 
1945.

Jim




>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
>