[ARC5] TN 1B/APR-1 and TN 2B/APR-1 Military Radio Tuners

[WA5CAB at cs.com]

You're right.  I didn't go back quite far enough.  And also, the ARC was in 
between the P-540 and the ARC-1 (unlike in the AN system, the suffix number 
indicated a later mod, contract or both).

In a message dated 3/23/2011 4:38:17 PM Central Daylight Time, 
jmfranke at cox.net writes: 
> There was the ARC-1 as well. Yes, the designation ARC-1 was changed to 
> the 
> familiar VHF transceiver, but the APR-1 started as the ARC-1 (SCR-587). 
> However, tuning units from the ARC-1 were not directly compatible with the 
> 
> APR-1 and APR-4 because they lacked the socket for the motor drive 24Vdc 
> pin. Otherwise, they were compatible. The field change required one to 
> drill 
> the matching hole in ARC-1 tuning units. And, there was the receiver that 
> started it all, the General Radio P-540 test receiver designed by Don 
> Sinclair.
> 
> John WA4WDL.
> 
> 
> --------------------------------------------------
> From: <WA5CAB at cs.com>
> Sent: Wednesday, March 23, 2011 4:46 PM
> To: <arc5 at mailman.qth.net>
> Subject: Re: [ARC5] TN 1B/APR-1 and TN 2B/APR-1 Military Radio Tuners
> 
> >Actually, there is one more model in the mix that no one has mentioned 
> >yet.
> >AN/SPR-1.  Same main frame containing the IF and audio strip and power
> >supply as the one in AN/APR-1, different antennas.  It replaced the RDO. 
> >There
> >were also two sets of plug-ins, the low numbers marked /APR-1, and the 
> >high
> >numbers marked /APR-4.  They are interchangable other than the earlier 
> >ones
> >don't have motor drive sweep.  And by nomenclature there is a fifth one,
> >AN/ALR-5.  Same receiver mainframe as late AN/APR-4 but three-band 
> plug-in
> >tuning unit CV-253/ALR.  It only covers 38-1000 MC.
> >
> >If anyone wants any of these units, I some some of it, including manuals.
> >No antennas, though.

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480