The AM Forum

Can anybody point me to the correct chain that is used on the band change mechanism for the National Nc-300 receiver?
 I have tried a few different 'new' chains, and I believe the ones currently being made are of a slightly different pitch or size, compared to the remains of the original chains.
 So I'm probably looking for some new-old-stock type of deal, someone who has a reel of this stuff dating from 50 years ago.
 ANYONE?
 --... ...--

Hi,

I don't know what the correct chain is but if you know its dimensions try matching them to the many varieties available at McMaster Carr here:

I would think a "standard" size was used even back then!

https://www.mcmaster.com/products/ball-chain/

-Chuck

The new ones are all metric. You can substitute, but the drum will not be in alignment on all bands.
Maybe someone has a parts unt?

  You might check with these guys:
https://www.ballchain.com
  Made in the U.S, apparently, and the sizes they list are given in standard SAE values, not metric, although they do indicate the metric equivalents.

This would make an interesting episode of “How it’s Made”

"Wirelessgirl.com" discusses this item in her page on NC-303 but has no source. 

An Amazon search for "ball chain" yielded a lot of results and sizes (of balls, I presume) 2.4mm, 3.0mm, 3.2mm, 4.5mm, #10, #8, etc.  The pitch is likely going to be the bugger.  If you can match the ball size, perhaps you can interpolate/approximate the pitch size in the photo.

if you find a suitable chain, please post the source.
Regards,
Russ
KW6T

Have a look guys!

https://www.ballchain.com/chain-sizes/

Speaking of balls and chains:

You can almost smell the cigarettes and the Southern Comfort.

:-)


https://www.youtube.com/watch?v=X1zFnyEe3nE

As I posted back on May 5th, further up the thread.
Never saw a reply from the OP, so I don't know if it worked for him.