Hi Ken

Many thanks about not turning those rods! I don't recall reading in the manual they were push/pull, but maybe I missed it.

I decided to take the receiver to a friend's house that lives on the tallest hill in the area (about 5 miles away) as I live in a valley surrounded by hills.

I easily picked up 6 or more stations (mid afternoon) with the DU-1 loop, two of which almost blew my headphones off. From my house, I'm lucky to hear one.

Also, some of the noise I was hearing was not present, another indication that my local environment is part of the issue.

As it stands now, I'm not going to do the alignment. Ray does have a point that these radios are 85 years old, although the IF cans in this radio are adjusted via trimmer caps, not slugs.

All caps in the radio were replaced a few months ago.

73 Mark K3MSB

On Mon, Aug 18, 2025 at 4:04 PM kgordon2006 <kgordon2006@frontier.com> wrote:

First of all, DO NOT twist those rods!!! They are meant to move only vertically.

Secondly, internally, they are literally soaked in beeswax and can be stuck. They SHOULD slide fairly easily up and down, but at this late date, they probably won't.

You may have to remove each IF can, remove the outer "case" and warm the beeswax until the rods move easily.

The selectivity improvemt with all three rods in the "UP" condition will be very noticable.

As far as sensitivity is concerned, the can caps are ALL defective by now. Trust me on this!!! You must either restuff them ALL with new caps, or simply replace them. I use 0.47 mfd metalized film 400 vdc caps.

The "ARC-5" receivers I have restored measure a sensitivity of less than 1 microvolt on AM, and even less with the BFO on.

I have never, yet, had to replace even one resistor in any of my receivers.

See this youtube video:

https://m.youtube.com/watch?v=vlz83QXM66A&pp=ygUFVzdFS0I%3D

Ken W7EKB

Sent via the Samsung Galaxy S21 5G, an AT&T 5G smartphone

-------- Original message --------
Date: 8/18/25 07:13 (GMT-08:00)
To: Mark K3MSB <mark.k3msb@gmail.com>
Subject: [Milsurplus] ATA ARA
Subject: [MRCA] ATA ARA RX Alignment Question

I'm thinking of aligning my 500 to 1500 Kc receiver.

Page 41 of the manual says to raise the protruding bakelite rods (of the 3 IF transformers) until they snap into the up position.

Delicately playing with one of them, it seems rather fragile, and I have to use a small pliers to move it -- I'm not sure what tool they used back then.

It didn't want to move either way, and I was leery of giving it a good twist for obvious reasons. The other two seem just as delicate.

The radio plays but it a bit lethargic -- i was thinking of just doing an alignment with the rods as they were (although the manual frown on that)

Comment from anyone that's done an alignment on this RX before?

73 Mark K3MSB