[Milsurplus] military use of the 180L-3

[Ray Fantini]

I know you know the numbers and you certainly were right and I was wrong about it being a switch wafer instead of jumpers being the difference on the C-1398 (38 head) and the C-3428 (38A head) but I have a 180L3 tuner that I have been using with my current ARC-38 and before on a 618S1 and it works great. The wiring diagram for the antenna tuners from the NAVAIR 16-30ARC38-502 book dated 30 June 1958, Changed 15 October 1971, page 161, figure 7-22 AN/ARC-38 External Wiring Diagram is almost identical to the Collins instruction book 520-5754-00 15 October 1957 for the 618S-1 and 618S-4.  Page 8-27, figure 8-26 shows maybe a flip between 9 and 15 on the 180L or G and R on the CU-351 but I do not recall having to do this when I changed from the 618S-1 to an ARC-38.
I have a couple part 180L3 that are clearly civil use because they have FAA acceptance tags attached to them but the 180L3 I currently have attached to the working 38 has no FAA tag but a small metal tag attached above P102 that says “ Coupler, Antenna Type 180L-3, 5821-333-8518, SER-AF63-134, 522-0092-004, AF33(657)9637” US acceptance stamp and “MFR 13499” the ARC-38 transceiver I am using this with is a “RT-311/ARC-38, NOas 57-438 “ same US acceptance stamp as the tuner followed by”1079COL” I am assuming this to be a military use 180L-3. Perhaps the 618S-1 was never used on any Navy aircraft but the 618S1 and 180L was used on other Military aircraft. There is both an ARC-38 and a 618S-1 along with a 180L3 installed on Truman’s Douglas VC-118 that not only served as his presidential airplane but was used for VIP flights up to 1967 and currently is on display at Wright Patterson. The real question is if the plug P-102 on the 351 and the 180L are different. But as far as functionality I do not see any real difference, and in the case of an aircraft that originally had a 618S and was upgraded to an ARC-38 or 38A they may have been paired?
Ray Fantini KA3EKH