Carver C-19 Pre-Amp blowing fuses

Odysseous

Hi guys,

I hope somebody can point me in the right direction: I've been enjoying my Polk Audio SRS 3.1TL with my Carver equipment, but today, my C-19 Reference Tube Pre-Amp didn't turn on. I opened it up and noticed the 1/2 Amp fuse was blown. I immediately ran to Radio Shack and bought 4 of those fuses. Drove home like a maniac and installed one of the fuses... a mini fireworks show happened inside the fuse and of course the fuse was blown... the other 3 fuses suffered the same fate... can anybody point me in the right direction as to what could be wrong? I'm not an electrician, but I'm not afraid of open stuff up, use a multi-meter to check resistance, etc and replace components using a soldering gun, I just don't know where to start checking...

Any help would be greatly appreciated!

Thanks!

dorokusai

Did you swap tubes?

Odysseous

Nope, I haven't even open the top lid in almost a year... it was working as of yesterday or the day before, there hasn't been any thunder storms or loss of power or anything like that, plus I have the C-19 plugged into a surge protector with a uninterruptible power supply. All the other components are perfectly fine and they're connected to the same surge protector. Nothing changed that I can tell, it just stopped working.

dorokusai

Doesn't sound like much troubleshooting to me....pop the top man. Check the outlet you're using as well.

nooshinjohn

I would give Rita's Vintage Audio repair a call... Most likely it is time for sesrvice and a refresh. While it is there, ask for Bob Carver to sign it.:D:cool:


Good luck with it.

Odysseous

I would send it to Rita, but didn't they raise their prices from $175 to about $350? I also have two TFM-45's that need repair but at $350 each + now my C-19, it's over $1,000. Whether it's worth it or not is irrelevant since I don't have $1,000 bucks to spend on repairing audio equipment... To get my components signed by Bob Carver, man, I'd love to, talk about pride of ownership! If I'd had the money I'd send it to Rita just to get them signed by Bob, even if there was nothing wrong with them.... but I can't do that in this economy.

Odysseous

Hi Dorokusai, I "pop the top" to change the fuses today, but since the new fuses blew up, I don't know where to start checking for the short. Is there a "most common" place where shorts occur in these C-19 pre-amps? I don't know where to start.. I could check every resitor, etc, but there's a ton of them!

dorokusai

Replace the fuses and connect it to a different outlet....in a different area of the house.

TNRabbit

If you're blowing fuses, there is obviously a short somewhere, and it's NOT between the unit & the wall.

Nothing looked cooked anywhere inside or on the board? If you continue to replace fuses without fixing WHY it's blowing, you'll end up destroying something more expensive than a fuse~

Fongolio

Are you replacing fuses of a similar type, not just value? Slo-blow with slo-blow? It still doesn't fix the initial problem but if you are putting a quick blow into a slow blow socket fireworks will happen.

Odysseous

OK, wait!! If it had a slo-blow fuse and I put in a quick-action fuse, it will blow?? I'm asking because I think that's exactly what I did. I don't know for sure if the old fuse was a slo-blow, but I do know the new ones are quick-blow.... If that does make a difference, why is that? I thought as long as the fuse is of the same amp rating it will behave the same... You might be on to something, though....

nooshinjohn

If you put a slow blow fuse in a quick blow location you will fry this thing beyond any hope of a reasonable repair, and may even end up cooking this thing forever. I do not want too sound insulting of your obvious intelligence, but the smart thing would be to bite the bullet and get it to Rita's before you really eff something up.

Odysseous

How can I tell if it needs a slo-blow fuse? Is there anything written on the fuse or the circuit board? (I didn't see anything) Or does anybody know if the C-19 requires slo-blow or quick-blow fuses? Thanks again for the advice.

gdb

If you join the forum linked below you'll have instant access to the service manual plus several engineers that know what's what.;)

http://thecarversite.com/yetanotherforum/default.aspx?g=forum

heiney9

Odysseous wrote: »

If that does make a difference, why is that? I thought as long as the fuse is of the same amp rating it will behave the same...

WOW, if you didn't know that; you need to stay far away from doing any repairs yourself. There is nothing in there a complete novice like you will be able to fix.

H9

restanim

nooshinjohn wrote: »

If you put a slow blow fuse in a quick blow location you will fry this thing beyond any hope of a reasonable repair, and may even end up cooking this thing forever. I do not want too sound insulting of your obvious intelligence, but the smart thing would be to bite the bullet and get it to Rita's before you really eff something up.

Nicely said....

Mike

Pycroft

If you ever want to get rid of that C-19 let me know, I'm on the hunt for one

I would like to add that I am new to tubes, and when you get a proper amp, you may change what you said about not hearing much of a difference. When I first heard tubes, I didn't hear a drastic difference (I may have been expecting something VERY dramatic). Over time, through critical listening, I'm starting to understand the difference a bit. That was ONLY with my basic tube preamplifier. I haven't given my new tube amp enough of a listen to appreciate yet. Enjoy!

James

nooshinjohn

Pycroft wrote: »

If you ever want to get rid of that C-19 let me know, I'm on the hunt for one


James

I already PM'd him about it.... DIBS!:D

George Grand

Replace the original blown fuse with the correct fuse, and then DO NOT plug it into that/any surge protector, but directly into the wall. Bet it works.

I have had several Carver power amps that wouldn't stop blowing fuses until they were plugged directly into the outlet. It was not limited to one surge protector either, so they were up to snuff (the surge protectors). The power amps worked just fine plugged into those surge protectors until one day they didn't, and that was the extent of it.

Odysseous

Hi guys, thanks for the help! For sure I'm not an electonics expert, but I did take 2 years of Electrical Engineering before switching to software engineering. Of course the first 2 years of EE are a lot of math and theory. So, yes, I don't know how to troubleshoot the problem with my C-19 (that's why I turned to the forums for help), but, no, I'm not a complete idiot that's going to plug this thing to the wall, turn it on, get some pliers and start pulling and connecting stuff to see where I see sparks!

I'm not interested in selling my equipment either. I know what I have and I know how rare, valuable, and complex my C-19 is, as well as the rest of my equipment: TFM-45 amps, SD/A 490t CD Player, TX-11b radio tuner and TD-1700 Cassette deck and obviously, my Polk Audio SRS 3.1TL.

I just want some help to troubleshoot it before I give up and send it in for repairs. If it's a short, most probably can be found without even having to plug the unit into the power outlet, so it's very safe and I can troubleshoot it with almost no risk. If the problem was the power supply, how can I test it? Remember, I've never done this, but I understand most of the concepts involved in building and troubleshooting electronics. Any help anybody can provide will be greatly appreciated!

Thanks!