frank9310
Full Member
Now dig this baby...
Posts: 146
|
Post by frank9310 on May 5, 2008 15:00:53 GMT -7
Just popped a set of the KT 66 Shuguangs in my Route 66 and have it running for about 30 minutes to get hot. So I set one of those Bias probes on to mA and it;s showing 38mA but when I go by the Rote 66 Bias notes from the Doc's site www.drzamps.com/biasnotes.html it says "Ground your Common lead to the chassis and carefully measure the RED/WHITE striped wire with your highest DC Voltage range. Adjust the bias pot till the Voltage at the RED/WHITE striped wire is at 475 Volts DC" However, if I set the mA to even the hotter range like 38mA the highest I get on the volts is 448. At 36mA it shows around 440v. Should I be turning up the heat more then to a higher mA?
|
|
|
Post by dixiechicken on May 5, 2008 15:17:42 GMT -7
"frank9310" - DC here!
This is Doc:s own reply by email to me - on this topic -- I asked about milliamps:
Doc:s reply is orange.
Cheers: Dixiechicken!
|
|
frank9310
Full Member
Now dig this baby...
Posts: 146
|
Post by frank9310 on May 5, 2008 16:21:19 GMT -7
Thanks DC but does the voltage sound normal at 442-448 set at 38mA? If I set it down lower to 32-34 it goes down to around 440v but the Bias Notes says it should be at around 475v so something doesn't seem right. It sounds ok but that voltage seems to be pretty far off from what the notes say it should be.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 5, 2008 19:19:14 GMT -7
|
|
|
Post by dixiechicken on May 6, 2008 6:09:38 GMT -7
|
|
|
Post by myles on May 6, 2008 14:04:29 GMT -7
Use a proper bias probe as there are too many factors that can affect things by dragging down the supply voltage on the B+
|
|
frank9310
Full Member
Now dig this baby...
Posts: 146
|
Post by frank9310 on May 6, 2008 18:16:48 GMT -7
Use a proper bias probe as there are too many factors that can affect things by dragging down the supply voltage on the B+ B+?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 6, 2008 20:14:28 GMT -7
Use a proper bias probe as there are too many factors that can affect things by dragging down the supply voltage on the B+ B+? The red and white wire.
|
|
frank9310
Full Member
Now dig this baby...
Posts: 146
|
Post by frank9310 on May 7, 2008 7:15:30 GMT -7
Ok thanks! That makes perfect sense then at 110volts from the wall x 4 = 440 and if it drifted to 112V x 4 = 448v which gives me a reading of around 36-38mA with the bias probe tool from Eurotubes. It's nice to have 2 multi-meters setup. One with the bias probe tool hooked up on mA setting and another using the max DC setting and testing the red & white wire. That way you can see how they correspond.
|
|
|
Post by Jim @94 Amps on Jun 16, 2008 20:38:33 GMT -7
Don't worry about the B+ voltage as long as you are between 28-42mA you'll be rockin'!
|
|