| Author |
Message |
    
Renagade
| | Posted on Friday, July 12, 2002 - 8:48 pm: | 
|
Hi folks,
Got something I've been curious about and figured some of you radio buffs could tell me. I have a Siltronix LA-550 that I got from an elderly gentleman a few years back. Down on the bottom of the front there is a knob that says Cathode Current with a arrow going clockwise that has Output Metering on it. When I bought the amp and ask him about it, he said "Don't worry with that, just leave it alone". At the time I didn't know a whole lot about amps so I was paying more attention on how to tune it properly and didn't push the point. A few times I've been tempted to reach down there and crank it up to see what happened....but I figured with my luck I'd blow the dang thing up!!
So, to satisfy my curiousity....what does it do??? My logical assumption would be that it does something to increase the current going somewhere...maybe the tubes?? If someone could explain what it's for I would appreciate the info |
Bigbob
| | Posted on Monday, July 15, 2002 - 6:48 pm: |
|
Go to "ask the tech" and ask tech 671,simple. |
Kirk
| | Posted on Tuesday, July 16, 2002 - 9:21 am: |
|
http://www.svetlana.com/docs/tubeworks.html
Everything you ever wanted to know....and then some!--73 Kirk AB8BC
|
409
| | Posted on Wednesday, July 17, 2002 - 3:36 am: |
|
You don't want to increase the cathode current beyond what the tube specs. call for unless you want to damage the cathodes coating causing shorter tube life. Check the specs. and see what MAX. cathode current is for your tube. |
2600
| | Posted on Thursday, July 18, 2002 - 3:13 pm: |
|
That switch ONLY CONTROLS THE METER FUNCTION, and should not affect the operation of the tubes. When clicked to the left, the meter READS cathode current on the tubes. When you click it to the right, the meter becomes a relative output indicator, and the knob sets the sensitivity, sorta like a SWR meter with JUST a calibrate side, and no SWR side.
73,
2600 |
707
| | Posted on Friday, July 19, 2002 - 11:51 pm: |
|
The meter may have a tiny Delta sign at about 40ma(the lower scale) or so. That's where the idle current should rest. |
|
