The Sig:X is down..

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midnightlaundry

midnightlaundry

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Was biasing and I smelled something.. I look and R162 is glowing red.. I shut it down and measured It at about 26R, one end goes to ground.
I flows millivolts and changes from like 88 to 115 mv when I switch from High to Low power.. BTW, that amp will go from 375vdc to 525 vdc on the Plates of the Power Tubes.. Badass.

The Amp is still working right now, but I need to get that switched out.

Anyone have a Sig so they can check the value on that Resistor?? It's at the 1 corner of the Board by the Power and Standby Switches..

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Good luck buddy. My SigX is also down and has been with my tech for several months now. I have similar issue like you. I have contacted fryette support and they were somewhat responsive at first and wanted some pictures of the pcb and description of the problem from my tech guy. We have provided them all the info but got no response after that point. Several emails over 2 months but nothing. I have even offered to buy a new PCB for my SigX but still no response. I'm from Europe so shipping to the USA is very difficult.
 
Sure would be nice if I could get a Schematic, even if it's redacted..
I sent a DM to David Phelge on TGP. He goes by Support on there. He got back pretty quick, but told me to send a pic to the website just like you.
I assume then he isn't technical, because it seems easy enough to look up the value for that 1 Resistor..
I'm tempted to just put a 2-Watt in there and call it good.
 
Good job dude :)

I have borrowed another SigX from my friend so my tech could get some measurements but it is still a very difficult job to get it repaired without proper schematic.
 
So far so good. Yeah, hard to fix things without technical info..
I just got lucky.. I had my face in there and smelled it right away. At least it was a Flameproof Metal Oxide high off the Board.
That thing was glowing red. It would have torched the Board. That's why they have them up high so it doesn't burn anything in case there's an issue..
A 2-Watt is twice the handling. Shouldn't have that problem again hopefully.

Months is a long time to wait. I hope you get yours back soon!
 
New development.. I can't believe I didn't check my own files.. I had a gut shot from 2016.. By all accounts that Resistor shows to be a 10R.. That makes sense why I ran out of Bias range when I switched in another set of tubes.. I have a 10R in a 2-Watt..

Morale of the story, take good gut shots of your Amp..

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midnightlaundry said:
Was biasing and I smelled something.. I look and R162 is glowing red.. I shut it down and measured It at about 26R, one end goes to ground.
I flows millivolts and changes from like 88 to 115 mv when I switch from High to Low power.. BTW, that amp will go from 375vdc to 525 vdc on the Plates of the Power Tubes.. Badass.

The Amp is still working right now, but I need to get that switched out.

Anyone have a Sig so they can check the value on that Resistor?? It's at the 1 corner of the Board by the Power and Standby Switches..

View attachment 288959
Click to expand...
What was the root cause of the R162 failure ?
 
Cannot say for sure. But one thing I did notice is that when switching between 100 watt to 40 watt, (I forget which way) there's a huge spike in Bias Voltage and then it settles to the set amount. Perhaps it was an accumulation of spikes that weakened it.

Haven't heard from Fryette yet. It's around noon on the west coast. Maybe they're taking Presidents Day off.. LOL
 
Seems to be more bias related hiccups in the past few years . Not just Fryette / VHT . Half power switches are increasingly part of the puzzle. Very interested in the final analysis of this issue . Hope they give you positive feedback .
 
Not attempting to stir the pot, but does Fryette not support these any more? I had strongly considered an Sig-X from a good friend before deciding to go with a Diezel…. But would still love another Fryette someday.

Seems odd to get the cold shoulder on a repair like this?
 
I did get a replay a couple hours ago, but it said to take to a Tech..
All I asked for was the Resistor value.. LOL
Take pics of your Amp because Schematics can be hard to find.
 
**DRB** said:
Not attempting to stir the pot, but does Fryette not support these any more? I had strongly considered an Sig-X from a good friend before deciding to go with a Diezel…. But would still love another Fryette someday.

Seems odd to get the cold shoulder on a repair like this?
Click to expand...
Fryettes are not for everyone. They don't have a saturated tone, they are more glassy and defined which is simply harder to play.
I like the Yellow Channel on the Sig because you can get good mid gain tones on 40 Watt. Out of the multi channel amps I've had, the mid gain tones always sucked. The Sig is the one that does it for me.

The Sig isn't as bright and Metal as the Deliverance, plus a single channel amp with 4-KT88's is just another animal. I never tried an Ultra Lead. I'm curious to try one whenever the new version comes out..
 
Fryette services everything they ever made.
Last I heard it is four people. That includes Steve and his wife. They are often slower at replies because they are busy doing something else.
 
I've owned 3 Fryette products over the years (CLX, PS and UL). All 3 of them have had similar issues (blowing main fuses on the circuit board). I still have the PS and it seems to be fine now. I am hesitant to buy another Fryette amp though.
 
With a little bit of horse trading I can borrow a Sig X for a weekend. I can open it up and get the resistor info if you absolutely need it .
midnightlaundry said:
I did get a replay a couple hours ago, but it said to take to a Tech..
All I asked for was the Resistor value.. LOL
Take pics of your Amp because Schematics can be hard to find.
Click to expand...
 
midnightlaundry said:
Fryettes are not for everyone. They don't have a saturated tone, they are more glassy and defined which is simply harder to play.
I like the Yellow Channel on the Sig because you can get good mid gain tones on 40 Watt. Out of the multi channel amps I've had, the mid gain tones always sucked. The Sig is the one that does it for me.

The Sig isn't as bright and Metal as the Deliverance, plus a single channel amp with 4-KT88's is just another animal. I never tried an Ultra Lead. I'm curious to try one whenever the new version comes out..
Click to expand...
You mention both the reason why I sold mine and why I miss mine too.
That yellow channel can almost out-Marshall a Marshall...and from clean to mean too. My favourite by far!
But that dryness, even with the saturation knobs high... I missed that 'goosed up' stuff I get from a Mesa Mark, 5150 and my Engls.
 
Just to follow up on this.. I pulled out my Meter and set it to Max Volts. So when switching from 40 watt to 100 watt, the Bias spikes to .295vdc where the recommended target is .135vdc.. The Bias Probe shows well over 100 ma's before it settles. I wonder if these spikes are to culprit? I have a 2-watt 10R in there now. So far all is good..

FYI, at .135vdc Each KT88 is flowing about 60ma's which is 70% Plate Dissipation calculated for 45 watts a Tube with a Plate Voltage of 531 vdc!

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