[Amps] Alpha 8410 using 4CX1500B - why?

[Roger (K8RI)]

On 10/31/2014 12:01 PM, donroden at hiwaay.net wrote:

I don't remember the tube designations any more as it's been 30 plus 
years since I worked on them, but we ran 200 - 250 KW as an oscillator, 
induction heater.  They were heavy (compared to an 8877, 4CX1500B, or 
4-1000A) and the anode was 16 to 18 inches long.  However you could 
easily lift one out of its socket by hand.  If you were in good shape 
and it wasn't so awkward to remove, you could have done it with one 
hand.  They were low mu Triodes with a  glass base about the size of a 
4-400 and that long anode about 4 inches in diameter. It just set down, 
inverted into the water jacket/socket and was clamped with a pair of 
hefty thumb screws.  They ran in the KHz range and didn't have to worry 
about a clean signal <:-)).  The cabinet with PS was about the size of 
my den, where I'm typing this.  "I'd guess the coils were 1/2" copper 
tube of maybe 15 to 20 turns, 8 to 10 inches in diameter, and a couple 
feet long. The caps were oil filled and roughly 18"H X 16"W X 6" thick. 
We used 2 to 4 of them.  I have no idea as to their ratings.  IIRC the 
plate voltage was somewhere around 12 Kv.   The biggest problem was sag 
in that plate coil as we needed a constant coupling along the length of 
the load.

I understand that part of the business is long gone.

73

Roger (K8RI)


> Quoting John Lyles <jtml at losalamos.com>:
>> Enjoy building amplifiers and don't make it a pain for yourself or 
>> your peers.
>> 73
>> John
>> K5PRO
>
>
> Good post John,
>
> Sounds like you had the perfect job for a ham radio operator.
> The biggest tube I worked with was a 4CX35,000 in a AM broadcast 
> transmitter.
> The socket had a jack to remove and insert the tube... Yours probably 
> required a chain hoist   LOL !!
>
> Don W4DNR
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>