Excellent tutorial and resources for the BC-191/375

[N0WEK]

In case you haven't seen this...

http://www.radioblvd.com/using_the_bc375e_today.htm

[WU2D]

I finally got most of one and will attempt this year, likely in the Fall. First I have to obtain the darned 211 valves.

[N0WEK]

I finally got most of one and will attempt this year, likely in the Fall. First I have to obtain the darned 211 valves.

It wouldn't look as cool but I've wondered if you could find a good substitute tube that isn't worth it's weight in gold and build some adapter sockets to install them in the transmitter with no changes to the transmitter.

[WU2D]

The 845 has an amplification factor of 5.3, the 211 has an amplification factor of 12, and the 838 has an amplification factor of 50. All have the 10V fils. Not much relief here in prices.

The 811A has a Mu of 160 so not likely.

Steve Russell WA1HUD says 812A's with the mu 29 are the logical choice and of course with some foolling with the fil voltage hookup.

I like the idea of triode connected 814's.

[PA4WM]

My first thought was, and excuse me for swearing in church, two pairs of Chinese made 211's...

But to my surprisse, when looking on ebay, I found a pretty stiff price.
Not as high as some NOS VT4C's but still.

Amazing how prices developed. In the 60's/70's, a lot of that surplus gear was to be found in west Europe. I know stories of barns piled with brand new boxed BC191's. Not to mention the enormous supply of VT4C's... They didn't cost anything. I recal stories of buying 10 for 20$
If we only knew then, what we know now, I could have opted for an early retirement 
Well, that doesn't help you offcourse, but you might have a look at those Asian ones.

Martin, PA4WM

[W7TFO]

I finally got most of one and will attempt this year, likely in the Fall. First I have to obtain the darned 211 valves.

One of these (eBay item 331173850564) makes it a lot easier to run on 160/75.

73DG

[kb3ouk]

RF Parts has 211s on their website for $35 each, I'm assuming they are Chinese. If you have a transmitter that isn't in really good shape and therefore aren't afraid of doing some modifications, the Russian GM70 might be a possible replacement. Cheaper than 211s, but you will need a different socket and the GM70 has a 20 volt filament. You can use an 813 socket for the GM70, you just have to make the one pin hole larger. The mu of the GM70 is somewhere around 7, the interelectrode capacitances are pretty close to those of the 211, the only thing I couldn't quite match up were the curves (the Russian graphs were hard to understand). Seems that even the audiophools use them in place of the 211 (some even seem to think the GM70 is better).