[Boatanchors] [National] National NC-100XAM? (long)

[Peter A Markavage]

I believe V-106 should be listed as a 6F8G.
Pete, wa2cwa

On Sat, 23 May 2009 23:22:10 -0400 Bob Young <youngbob53 at msn.com> writes:
> 
> I just bought a NC-100XAM on ebay, at a pretty good price and very 
> nice cosmetically and mechanically, I went and picked it up in the 
> boatanchor hauler. I can find no info about this radio, Raymond S. 
> Moore's 4th ed has it listed but no info anywhere even though I 
> found a very comprehensive list of National Catacomb radios from 
> AMfone under receivers.
> The tag says NC-100XA but it also has another tag that says type: 
> NC-100XAM, ser # 13, 8-8-40 and order # is blank. It was supposed to 
> have been made for the Navy, it's black wrinkle and is a rack mount. 
> It seems similar to the army NC-100ASD except for it's range: .54 to 
> 30 Kc like most of them. It has the push pull switch (for the 
> meter?) instead of a toggle switch, it's got binding posts for the 
> antenna hookups. All tube sockets are porcelain and the tube 
> compliment is:
> V-101 6J7 (supposed to be 6K7?)
> V-102 6J7
> V-103 6J7
> V-104 6K7
> V-105 6K7
> V-106 6FG8
> V-107 6C8G
> V-108 6J7
> V-109 6F6
> V-110 5Z3 (I think, no number but looks like one).
> The seller powered it up but I assume didn't hook up a speaker and 
> there was a BIG fuse in it. This back has E102: speaker out (500 
> ohms?) and E103 which I assume is for a field coil, (one of the pins 
> comes from the power transformer then to the one of the rectifier 
> tube pins, haven't traced the other one). I can't find a schematic 
> for it. The chassis layout is also different than the regular 
> NC-100XA's. It has 4 electrolytics, 4 mf 600 V cans. and the if 
> transformers are laid out differently. The power transformer says 
> NC-100F on it. My main question is do I need to hook up some kind of 
> a choke or power resistor to E103 or can I power it up with just a 
> 500-8 ohm transformer from the speaker output and leave nothing 
> connected to E103? The string that moves the indicator needle is 
> also broken.
> 
> ks,
> 
> Bob
> KB1OKL