[Milsurplus] TCS Tx and RX identity

[WA5CAB at cs.com]

Dave,

OK.  Thanks.  

I have or have had examples of receivers and transmitters of TCS-5 and most 
if not all numbers through -14 (and have seen -15), and all have nameplates 
(else how would the model number be known?).  So from that I think that we 
must conclude that your 51Q-1 receiver was either part of TCS through TCS-4 
or built on a receiver-only order.  I have evidence (the 56Q manual) that 
the Navy bought at least a few stand-alone transmitters.  They were supplied 
with one of two different AC operated supplies (which I have never seen an 
example of).

As to why the receiver has what I assume to be the later production etched 
panel, I don't know.  As I mentioned earlier, the TCS-4 manual still shows 
engraved panels.  But that could be merely because they used the same photos 
rather than re-shoot everything just because of the lettering method change. 
 The lettering change wouldn't have mattered to anyone but a collector.  
:-)

I'm inclined to agree with you about the magnitude of the serial numbers.  
But I don't have any production figures by model.  It is possible, since it 
appears that Navy nameplates didn't appear until TCS-5, that Collins 
incremented numbers continuously from the original TCS order until the TCS-5 order. 
 That would make sense as the nameplates that were present all must have 
said 51Q-1 or 56Q-1.  In the relatively few examples where the Navy let a 
second or subsequent contract without incrementing the "Model" number, serial 
numbers ran sequentially through the orders.  In other words, TCS-12 
transmitter serial number 9363 (qhwew the RF Ammeter wiring changed) is unique.  
Unlike common Signal Corps practice where you also had to know the Order Number.

On the "-1" as in "56Q-1", I think it was fairly common Collins practice to 
start everything off at -1.  The Signal Corps mostly shifted over to that 
thinking (everything started life as "-A") circa 1942.  TMC was another 
(later) company that did it.  But in cases where it didn't matter to be that 
specific, the hyphen and suffix number was sometimes dropped.  As the method of 
lettering the front panel (except for the need of the bezel behind the 
transmitter antenna roller coil) had no effect on the fit or function of the 
panel, my guess would be that they didn't see any need to call your receiver a 
51Q-2 just because the lettering method changed.  

In a message dated 11/28/2010 12:54:21 AM Central Standard Time, 
davprin1 at optusnet.com.au writes: 
> Once again, you are spot-on, Robert.
> 
> Came back from my weekender this afternoon and dug out the 
> two units. Removal of the cases show that neither the tx or 
> the rx have screw holes for the ID plates looking at the 
> rear of the front panels.
> 
> However, on the rear of the chassis, both have small Collins 
> ID plates. The tx is Model 56Q-1 with serial number of 12364 
> and the rx is Model 51Q-1 with serial of 22259. The receiver 
> also has an orange U.S. Navy stamp (Anchor with US) on the 
> back. Serial numbers seem awfully high!
> 
> Have not found anything with a date on it as yet.
> 
> I did bring back from my weekender storage, a TCS-12 rx with 
> a serial of 379 on Contract NXsr36727. It has a couple of 
> inspection dates of 24 and 25 Jan 1944.
> 
> Many thanks, Robert.
> 
> 

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