[Milsurplus] [ARC5] Vintage LF/MF Fun with my BC-453B

[Thomas Adams]

One modification to the BC-453 that I'd highly recommend...

The tapped antenna input coil is a problem; in many situations it allows unwanted ground loops
that greatly increase noise sneaking in from the AC power line.

On one set I had, I pulled out the antenna coil and disconnected the tap. I then replaced it with a
link coil of maybe 20 turns wound over the coil. The plug in terminals can be configured to allow
the new link coil to be connected to the antenna input.

The noise level went down dramatically, and after some realignment the set became a first class 
NDB hunter. 


Mr. T.


-----Original Message-----
From: Dennis Monticelli <dennis.monticelli at gmail.com>
Sent: Nov 19, 2025 3:15 PM
To: Mark K3MSB <mark.k3msb at gmail.com>
Cc: ARC5 <arc5 at mailman.qth.net>, Military Radio Collectors Association (mrca at mailman.qth.net) <mrca at mailman.qth.net>, List Milsurplus <milsurplus at mailman.qth.net>
Subject: Re: [Milsurplus] [ARC5] Vintage LF/MF Fun with my BC-453B

Mark, 
That is a fun thing to do.  10 yrs ago I did the same thing with a rebuilt BC-453B.  One tip I will pass along is to use batteries if you can, especially the B+.  I ran eight 9V batteries for B+.   Divorcing the receiver from the AC line reduces noise pickup from all the crud that modern electronics dump into the line.  It was a significant difference in my situation.  Also if you haven't already, adjust the IF transformers for looser coupling by pulling up on the tabs.  This will reduce the noise BW.
 
Dennis AE6C


On Wed, Nov 19, 2025 at 12:25 PM Mark K3MSB <mark.k3msb at gmail.com (mailto:mark.k3msb at gmail.com)> wrote:
Hi Everyone
 
For the past 2 years I've been using my RBA receiver for vintage LF/MF fun, and have logged over 200 NDBs each year.   This year I decided to use my BC-453B receiver.   It's been recapped, and all out of tolerance resistors (sans one....) have been replaced.
 



Since early November,  I've logged 52 NDBs.   I'm hoping to log 100 this listening season (which runs through March).
 
73 Mark K3MSB

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