MrMojoRison Posted January 7, 2016 Share Posted January 7, 2016 Hi all, I'm new here and I tried using the search for help but couldnt find much. I've found this Hawk GA 25RVT. (6V6 version w/ 15" 8 ohm) When turned on the jewel lights up and all the tubes light up but the amp is dead silent. Passes no signal. So i pulled the output transformer and it has a failed primary. So I'm looking at getting a new one of those. But while I'm doing that I figure I should probably do the caps too. They look good and hold juice (i had to discharge them). S Is there a good resource out there that can explain to me how to test these caps and where can I find replacements. This is the first amp I've ever torn into so anything helps. It would be nice to get the transformer and caps from the same place. Also, i was told that if i dont replace the caps and put a new transformer in it a faulty cap could fry the transformer. True? Again, I'm new to this whole thing so your patience is appreciated. Thanks Jake Link to comment Share on other sites More sharing options...
sparquelito Posted January 7, 2016 Share Posted January 7, 2016 Jake, I have a good friend here who builds amps and troubleshoots them as well. I'll PM you his email address, if that's okay with you. sparky Link to comment Share on other sites More sharing options...
MrMojoRison Posted January 7, 2016 Author Share Posted January 7, 2016 Jake, I have a good friend here who builds amps and troubleshoots them as well. I'll PM you his email address, if that's okay with you. sparky Yeah if he doesnt mind newb questions that would be nice. thank you sparky! Link to comment Share on other sites More sharing options...
sparquelito Posted January 8, 2016 Share Posted January 8, 2016 Yeah if he doesnt mind newb questions that would be nice. thank you sparky! My amp-builder friend is Patrick Gentile. His Facebook address is https://www.facebook.com/patrick.gentile.56?fref=ts His email is patrick.gentile@gmail.com Link to comment Share on other sites More sharing options...
badbluesplayer Posted January 8, 2016 Share Posted January 8, 2016 You'll want to replace the electrolytic caps if they're more than about 10 years old. Don't bother trying to test the caps. It's very complicated and that's not what's normally done. Just replace them. Amplified Parts has most stuff. As far as the power xfmr goes, Mercury Magnetics makes one in their ToneClone line that lists for $197. Call Patrick Selfridge at Mercury Magnetics. See here - http://www.mercurymagnetics.com/pages/mainframe.htm I didn't see any made by Classic Tone. I didn't see any at Mojotone, Allen Amplification, Amplified Parts or anywhere else. If you have any other questions, ask here or on Facebook at Tennessee Amplifier Link to comment Share on other sites More sharing options...
MrMojoRison Posted January 8, 2016 Author Share Posted January 8, 2016 Thanks everyone. The old caps are RCA 15uF 450V. They are the kind that are in a paper tube opposing each other. 2 tubes, 4 caps in total. I was referred to triodeelectronics.com and found some sprague 16uF 475V caps. They don't look the same as the originals but have (from what I understand) acceptable values. http://www.triodeelectronics.com/16uf450sprag.html As for the output transformer. Yeah I saw that one at mercury magnetics but man thats a lot of dough! You would think there would be an alternative out there somewhere. The search continues and thanks for the help and guidance. cheers Link to comment Share on other sites More sharing options...
MrMojoRison Posted January 9, 2016 Author Share Posted January 9, 2016 You'll want to replace the electrolytic caps if they're more than about 10 years old. Don't bother trying to test the caps. It's very complicated and that's not what's normally done. Just replace them. Amplified Parts has most stuff. As far as the power xfmr goes, Mercury Magnetics makes one in their ToneClone line that lists for $197. Call Patrick Selfridge at Mercury Magnetics. See here - http://www.mercurymagnetics.com/pages/mainframe.htm I didn't see any made by Classic Tone. I didn't see any at Mojotone, Allen Amplification, Amplified Parts or anywhere else. If you have any other questions, ask here or on Facebook at Tennessee Amplifier thanks! looks like I'll be buying from Amplified Parts. They have everything I need and in stock. Link to comment Share on other sites More sharing options...
badbluesplayer Posted January 9, 2016 Share Posted January 9, 2016 Thanks everyone. The old caps are RCA 15uF 450V. They are the kind that are in a paper tube opposing each other. 2 tubes, 4 caps in total. I was referred to triodeelectronics.com and found some sprague 16uF 475V caps. They don't look the same as the originals but have (from what I understand) acceptable values. http://www.triodeelectronics.com/16uf450sprag.html As for the output transformer. Yeah I saw that one at mercury magnetics but man thats a lot of dough! You would think there would be an alternative out there somewhere. The search continues and thanks for the help and guidance. cheers That cap looks like a "firecracker" cap. Amplified Parts has some of those. HERE. I'm not sure if they have what you need. You can use the existing mountin clip or use zip ties to hold them. And the output transformer looks like it's from 1963. Link to comment Share on other sites More sharing options...
MrMojoRison Posted January 9, 2016 Author Share Posted January 9, 2016 That cap looks like a "firecracker" cap. Amplified Parts has some of those. HERE. I'm not sure if they have what you need. You can use the existing mountin clip or use zip ties to hold them. And the output transformer looks like it's from 1963. I dont see any of the firecracker style that are close to the values that I need. Whats in that photo is the cardboard housing that have two caps inside of it. They are butted up to each other and then wrapped in that paper tube. so they are two separate caps. I was thinking I could go with something like this. https://www.amplifiedparts.com/products/C-ET16-475-FT They are a different style but the values are almost spot on. I would have to be a little creative with the mounting. Any reason I couldnt go this route? Link to comment Share on other sites More sharing options...
badbluesplayer Posted January 10, 2016 Share Posted January 10, 2016 I dont see any of the firecracker style that are close to the values that I need. Whats in that photo is the cardboard housing that have two caps inside of it. They are butted up to each other and then wrapped in that paper tube. so they are two separate caps. I was thinking I could go with something like this. https://www.amplifiedparts.com/products/C-ET16-475-FT They are a different style but the values are almost spot on. I would have to be a little creative with the mounting. Any reason I couldnt go this route? That looks good! I'm not sure how the caps are grounded in there but if you could separate the grounds from the different caps so that they are "star grounded" or, better yet, grounded to different independent locations, then the amp will be a little quieter. Link to comment Share on other sites More sharing options...
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