[Milsurplus] Was ARC-3, now ARC-4

[Jack Antonio]

Marty mentions the AN/ARC-4.

I made one play, this was maybe 4 years ago or so. I've
cabled it up, but need to finish up the display.

Receiver is somewhat deaf, best I could hear was about 15 uV from
a Model 80 sig gen. But then there is no RF stage, just a mixer
down to a broad IF.  Marty was lucky in his plug and play, mine
needed a wholesale paper capacitor replacement.  Squelch is
kind of "rubbery", not a positive action, sounds almost like
a volume control is being turned up and down. It is entirely
possible the receiver still has some problems waiting to be fixed.

Transmitter is pretty straighforward. Uses 1614s, which are metal
6L6 selected for RF, but somwhere in the manual it mentions that
6L6 can probably be substituted. IIRC, the transmitter tuned up
with no problems.

There seems to be 4 stock frequencies that were supplied with
the rig, in the 140 to 142 range, but I have a factory original
WE703 for 144.36.

Interesting thing is the similarity in plug connections to
the AN/ARC-1. The rear plug is the same between the two, just
turned over.  The MT-230(?) rack has a label noting this fact.
One of the rainy day projects is to see how close the pin connections
are.

And yes, I understand the reference to the Douglas Racer.

On the ARC-3, the tuning mechanism is mostly out of sight,
but yes, it is satisfying after some extensive troubleshooting
to cycle the mechanism and see the dials stop at the right
frequency.

Jack

Jack Antonio WA7DIA
scr287 at sbcglobal.net

Unserviceable but Repairable wrote:
> Many folks know the ARC-4.  But no 1st-hand testimonials in the thread.

>  For years I've been wanting to see the ARC-3 robo-tune feature work!
>  Did W7dia read this?