[TenTec] Argosy 525/525D mixers and serial numbers revisited

[N4NT]

My Argosy II 525-D is serial 52501892  The front panel has the "Argosy II" 
label.

On the RF Mixer Board, U2 is physically a very small black 4-legged round 
device with the following label: 87clk32  I cannot determine if the l is 
actually a numeral one, the letter L or the letter I)

My schematic specifies U2 as an ND487CI (or CL or C1).

73, Mike N4NT

----- Original Message ----- 
From: "Kevin Purcell" <kevinpurcell at pobox.com>
To: <wa3fiy at radioadv.com>
Cc: "Kevin Purcell" <kevinpurcell at pobox.com>; "Discussion of Ten-Tec 
Equipment" <tentec at contesting.com>
Sent: Wednesday, September 26, 2007 6:04 PM
Subject: [TenTec] Argosy 525/525D mixers and serial numbers revisited


> Thanks for your replies.
>
> I'm writing another reply but I realized that you help fill in more
> of the serial numbers on my list. See my old post
>
> <http://lists.contesting.com/archives//html/TenTec/2007-05/
> msg00036.html>
>
> So the list of mixers versus serial numbers in now includes yours.
>
> 525  00721 1496     VE7BGP
> 525  ????? PN ring  KW7CD
> 525  01188 mixer?   WA3FIY
> 525D 01611 ND487C1  N7WIM  (with Argosy front panel)
> 525D 01810 ND487C1? WA3FIY
> 525D 02497 ND487C1  N7WIM  (with Argosy II front panel)
>
> But we're missing the mixer type in your 525. It would (help) confirm
> the theory that the 1496 was dropped after S/N 00823 and that the
> later 525 used a PN diode ring as mentioned in Dretea's article in
> Ham Radio on Argosymods.