Discussion in 'Tube Audio' started by outlawmws, May 15, 2005.
Weston 981 Type 3
Almost all of these link are broke and don't work.
I'm over in Rocklin, off hwy 65. Just rebuilding a couple of Fishers now. ( New to Tubes ) 800c and 59A and 59T in a Futura VI Modern Walnut console.
Just picked up a Precision Apparatus 920 tube tester, but it has 2 wires off I'm trying to find where the loose ends go. One comes off the main tube and the other off the F dial.
Do you have any experience with Precision Apparatus? I think I have the schematic but can't quite figure these wires out and why they are off. One that is off has a ring connector.
Anyone else on the thread have Precision apparatus 920 they can take a picture of underneath?
Brown wire is off the Main Tube pictured( 2132 ) and the Black wire is off the F slector switch Pictured (2128)
Seco 107 serial number 1001. Designed by my Dad, Ed Bramsen, founder of Seco in the mid 1950s, and in my possession since he passed in 1973.
Ski Brain- Track down that schematic! Or if you can't, look up the pinout of that tube and identify which pin that brown wire is connected to. Also, does the tester work at all with these dangling wires?
Yes the tester does work with the wires discounnected. I was just afraid if I inserted a tube to test that needed that connection it might blow the tube.
I'll see if I can get the schematic and track down the connection.
Sorry for the late reply work went crazy on me and I had to really concentrate for a while.
I'm in the Baltimore, Maryland area, Pasadena to be specific (South-East side). I have a Hickok 6000A that was calibrated a few year back and works well. I'd be happy to try to accommodate the 'testing' needs of any local AK'rs...... Tom D.
Thanks for the Offer Wharfcreek, but I'm on the other side of the US. Sacramento CA.
I used to get out there fairly often.
I need to get back to this stuff, but work has me going crazy and now I think I'm going to change jobs. ( more learning )
here's some links,
http://dbl.musicweb.ch/schematics/Music Instruments/Amplifier/Other Homebrews/
Happy to help others verify tube status.
Atwater, ohio (on stark-portage co.line.),alliance,canton,hartville areas. hickok 533a with 1961 chart, sencore tc-162,knight kg-600b. Have a lot of used & nos tubes;a lot of old radio tubes, 5-6-7 pins,loctals,octals, 7&9 pin minis. Bunch of old tv tubes also, used & nos. Contact me with needs, will see what I can dig up. Functional powerstat 116bt variable autotransformer / variac with integrated DBT for awakening the dead safely.
I have the exact same issue with the exact same tester. Dis you ever get to the bottom of this?
I have not found this out but just started to investigate again. I just need to find my schematic as I did trace the wires back to the connected source. I did talk to an old tube guy and he said that some were left off for RFI ??? with the solder on the one and the ring on the other I have a hard time with that. ( These could easily short on something if the box was moved adn plugged back in. I'l see if I can find my schematic again and that should help. If I can look up the pictures of the origin point of the wires I'll attach them here.
Here is the website that has the Schematic: ( Thanks to Chris Old Radios )
I'll go look at it tonight and track the wires down and where they go hopefully. 1 is probably ground.
RFI in a tube tester? I'd love to hear the back story on that!
I've heard this, that's why some testers have Ferrite beads on some of the leads. I think some tubes can self oscillate.
It is possible the flying lead is to ground the faceplate, wedged between the faceplate and case
I think you maybe correct on the one lead. Even though this was a while back when I pulled it open to clean it up. I think that is where the one lead was stuck.
I really wish I could find someone with one of these to take a picture of their unit and maybe I could track down the connections. The schematics are not easy to figure out and are limited in scope. Or I have no idea how to read the one switch with 9 layers of connections on it. Help me Mr. Wizard!
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