[MRCA] collins plug

[Mike Morrow]

> Never one to argue, and such, but been using the "book" and
> after some half-dozen systems wired, all worked, or are working,
> with no issues..... yet?  I would be curious to know the minutia
> of these errors and compare to what I have.
>
> Jeep K3HVG

The most common and comprehensive maintenance manual for the AN/ART-13 series (especially the AN/ART-13A (T-47A) and the AN/ART-13B (T-412) is USAF T.O. 12R2-2ART13-2.  The edition of 30 MAR 56 is common in both physical and pdf format.

The Figure 8-42 schematic for the AN/ART-13A contains the drawing flaws to which I earlier referred.  I noted in my original post that those flaws are INTERNAL to the T-47A and do not impact external wiring shown for the C-87, CU-24, CU-32, or DY-17.  To observe those flaws, compare Fig. 8-42 from Mike's URL I gave below to the uncorrected Fig 8-42 from an original manual.  The flaws are mostly found to the right of the vacuum relay K-102 in the T-47A.

Figure 8-43 is the AN/ARC-8 unit interconnection diagram combining the AN/ART-13A with the AN/ARR-11 (BC-348-Q or -R), among many other things.  That figure is correctly reproduced in original manuals.

For the AN/ART-13B there is also the Fig. 8-44 schematic diagram, similar to Fig. 8-42 for AN/ART-13A.  Fig. 8-44 has obvious drawing corrections made where Fig. 8-42 has its flaws.  Unfortunately, whoever produced Fig. 8-44 assigned S-117 to the T-412's new extended low frequency switch.  But S-117 had already been assigned to the dynamotor control power interlock switch that was added to the T-47A design.

For the OP Dennis:  The best source of wiring information is the AN/ARC-8 diagram Fig. 8-43 in USAF T.O. 12R2-2ART13-2.  The almost complete T.O.* may be downloaded here:

  https://www.radionerds.com/index.php/AN~ART-13

Fig. 8-43 clearly shows the connections between:

U-6/U   C-87  TO T-47A
U-7/U   T-47A TO DY-17
U-8/U   T-47A TO C-87
U-9/U   DY-17 TO T-47A
U-10/U  28VDC TO DY-17
U-11/U  T-47A TO CU-32
U-12/U  CU-32 TO T-47A

* I believe that the T.O. pdf is missing Fig. 8-42, but a copy of Mike's work is available at the URL cited above.

Mike / KK5F

On 08/17/2020 1:20 PM Mike Morrow <kk5f at earthlink.net> wrote:

> The overall system schematic diagram in all known AN/ARC-8
> maintenance manuals using the T-47A was improperly reproduced
> on its original issue and never corrected. It has sections
> where some internal wiring headers for the T-47A/ART-13 are
> broken, shifted, and misconnected.
>
> One of the many many treasures on Mike Hanz's extraordinary
> website is that diagram, but which Mike painstakingly corrected
> for a flawless reproduction that he has posted here:
>
>  https://aafradio.org/docs/ART-13A_schematic.png
>
> This is much better than owning the original flawed diagram.
>
> It clearly shows the wiring of all connectors associated with
> the T-47A/ART-13. Such wiring is also applicable to the T-47/ART-13,
> and mostly applicable to the T-412/ART-13B and ATC/COL-52286A.
> (We were not favored with knowledge of exactly which transmitter
> is involved here.)
>
> Mike / KK5F