tube fanatic Posted July 29, 2015 Share Posted July 29, 2015 A thought about something we could do in this section if there's interest. How about an ongoing thread (similar to the great photography thread) in which folks could post their questions about issues they are having with their tube equipment. It could be anything from it not working properly to modifications and so on. Time to put in another 2 cents! Maynard 2 Quote Link to comment Share on other sites More sharing options...
Guest thesloth Posted July 30, 2015 Share Posted July 30, 2015 One such "modification" could be the removal of the old polarized power cable and the replacement to a safer grounded cable. A lot of times there is a small value high voltage capacitor from the power transformers primary winding to chassis ground, this "death" cap should also be removed. Next time I get a specimen to do this I will step by step the process and add it. How about an old amp that hasn't been used in a while. Maybe a small write up about how to reform the old capacitors. Or maybe even a complete restoration. I just did a Eico ST40 a couple weeks ago, it came out great. I might even go back and edit: https://community.klipsch.com/index.php?/topic/158445-caution-high-voltage/ I want to add that working on any amplifier without a transformer is a no no. Some of the old consoles just rectified the mains directly without a power transformer, they strung the heaters in series. These units are VERY DANGEROUS and should be fitted with a 1:1 isolation transformer for safety reasons. Quote Link to comment Share on other sites More sharing options...
juniper Posted August 2, 2015 Share Posted August 2, 2015 Heres one for you Maynard or anyone else! I think you might have some pictures of the belly of my Pilot amp. When I bias it sometimes the screwdriver slips past the external biasing screws into the chassis, I am I going to get zapped or did Pilot think about this in their design? The screw heads are small, the screwdriver when it slips only goes in about 3/8ths of an inch. Thanks!!! Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted August 2, 2015 Author Share Posted August 2, 2015 Pat, although I don't have your picture, here's a link to one of the underside of the same amp: https://www.facebook.com/JaBurgessAmplifiers/photos/a.327580570743355.1073741836.171241739710573/327580627410016/ In your case, the adjustment pots are mounted to a metal bracket (see the right side of the picture), so when the screw driver slips you are simply hitting that. However, it's always a good practice, when adjusting controls which allow tools to go inside the chassis, to use a plastic or other insulated tool. Click on this link, and then click on data sheet: http://www.onlinecomponents.com/gc-electronics-8195.html?p=11424012&utm_source=google&utm_medium=cpc&utm_campaign=Shopping%20Suppliers&utm_term=&utm_content=kQGNzIa8&ref=GoogleAd:Shopping%20Suppliers-GC%20Electronics&cshift_ck=9e439796-d3b9-4f7e-a3f3-a615e027a6becskQGNzIa8 It's a good idea to have a set like this available for making adjustments. An alternative is to get a 3/16" or 1/4" wood dowel and shave down the end to create a screw driver blade of appropriate thickness. Maynard Quote Link to comment Share on other sites More sharing options...
sasqwatch Posted August 18, 2015 Share Posted August 18, 2015 (edited) Well this isn't a problem with equipment or question about a mod , but I thought if I were to ask here someone with a question in those categories may find help with any potential answers to mine. My question is I would like to learn how to read tube amp schematics and gain a better understanding of tube amp circuits. does anyone know of any teaching aids, articles, websites they would like to share. Thanks in advance for any insight. Stacy Edited August 18, 2015 by sasqwatch Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted August 18, 2015 Author Share Posted August 18, 2015 Well this isn't a problem with equipment or question about a mod , but I thought if I were to ask here someone with a question in those categories may find help with any potential answers to mine. My question is I would like to learn how to read tube amp schematics and gain a better understanding of tube amp circuits. does anyone know of any teaching aids, articles, websites they would like to share. Thanks in advance for any insight. Stacy Stacy, I found these sites which may help you get started. In the first one, scroll down to the "Basics..." section and you can pick through the topics: http://www.funwithtubes.net/ Also, this site looks to be fairly comprehensive: http://www.electronicstheory.com/ Maynard Quote Link to comment Share on other sites More sharing options...
sasqwatch Posted August 18, 2015 Share Posted August 18, 2015 Thanks Maynard for the links i will check them out this evening. Quote Link to comment Share on other sites More sharing options...
Mikayates Posted August 31, 2015 Share Posted August 31, 2015 Well this isn't a problem with equipment or question about a mod , but I thought if I were to ask here someone with a question in those categories may find help with any potential answers to mine. My question is I would like to learn how to read tube amp schematics and gain a better understanding of tube amp circuits. does anyone know of any teaching aids, articles, websites they would like to share. Thanks in advance for any insight. Stacy Hi there, ultra new to this forum (very first post and all) and hope to both learn and maybe contribute where possible to the best of my abilities. Would like to recommend a series of videos on youtube done by a guy who goes by the name of Uncle Doug. His presentations go from the very basics to the more involved, and although his expertise is primarily with guitar based designs, the principles involved are all relevant and could serve as a great place to start understanding schematics... Just a suggestion . Cheers. Mick. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted August 31, 2015 Author Share Posted August 31, 2015 Well this isn't a problem with equipment or question about a mod , but I thought if I were to ask here someone with a question in those categories may find help with any potential answers to mine. My question is I would like to learn how to read tube amp schematics and gain a better understanding of tube amp circuits. does anyone know of any teaching aids, articles, websites they would like to share. Thanks in advance for any insight. Stacy Hi there, ultra new to this forum (very first post and all) and hope to both learn and maybe contribute where possible to the best of my abilities. Would like to recommend a series of videos on youtube done by a guy who goes by the name of Uncle Doug. His presentations go from the very basics to the more involved, and although his expertise is primarily with guitar based designs, the principles involved are all relevant and could serve as a great place to start understanding schematics... Just a suggestion . Cheers. Mick. Hi Mick and welcome to the insanity! Can you post the link to the full playlist of Uncle Doug's videos? As you said, an amp is an amp in terms of the basic principles. Where are you located, and what kind of equipment do you use? Maynard Quote Link to comment Share on other sites More sharing options...
Mikayates Posted September 1, 2015 Share Posted September 1, 2015 https://www.youtube.com/channel/UCuR4hQTXkG_KxozLxwPzEjQ Thanks wdecho, you beat me to it.! Yes, that link directs you to Uncle Dougs home page, just click on videos and bam, there you have it. Maynard, thanks for the welcome into "insanity", ha,ha.. There's nothing like a good challenge in life eh.?! As for me, well, Im located in Australia, on the west coast in a city called Perth. I'm into all kinds of music, and love it loud (much to my wife's disgust) .. I've recently just done a full revamp of my gear, consisting of a Cayin CS100A (KT88) integrated Amp, Yamaha CD player, Technics SL1200 turntable (a remnant of my last set-up) all being delivered with authority through a pair of Cherry RF-7ii"s... The system has had a serious amount of play-in time and is now sounding pretty close to my liking. I did replace a few pre-amp tubes earlier in the piece in an attempt to eliminate what i perceived as an overly bright delivery. I believe this had but a small influence and in hindsight, i think the system just needed it's own time to settle. Ah, patience is a virtue they say..... Again, thanks for the welcome.! Cheers. Mick. Quote Link to comment Share on other sites More sharing options...
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