DRRI possesion!!

[My Guitar Weeps]

What could possibly be the cause of the jewel light to severely dim?

Last night I noticed it. It was when I was playing and the amp had been on for a good hour. At times it seemed it was in tune with the sag, say on bass notes and heavy chords. Other times it was hard to tell. It was intermidate for sure. I've never noticed it before. I did change over to different power tubes and biased the idle current up a couple of milliamps, but that's it. Same wall outlet. Sometimes it would just dance a little and a couple of times it appeared to just about go out completely. I thought my eyes were playing tricks on me at first.

I plan on putting it through the paces again hopefully tonight, but it will probably be tomorrow evening. I'm certain my wife would be a bit upset if I spent our wedding anniversary trouble shooting an amp.........

[phantomman]

Could jus' be the bulb gittin' ready to head south.

It uses a GE #47 an' it's easy enough to replace. Unscrew the jeweled cover, gently twist the bulb a ¼-turn counter-clockwise then pull it out. Best to do it with the amp 'cold'.

Reverse the procedure when installing the replacement.

HTH

[My Guitar Weeps]

Thank ya sir!

I hope that's it. I get a little on egg shells when things start randomly going on after I've been poking around, know what I mean? It never fails.....once you start talkin' bout how well something sounds and how pleased you are with it now that you've sprinkeld on this mojo or that magic dust.........something goes wankers! (Sure seems that way in my camp.....lol)

[phantomman]

Well the pilot lamp on my new HRDlx started goin' wonky about a year after I bought it (omen of thangs yet to come?). I changed out the bulb for an NOS Tungsol and never had no further problems with it.

Think of an incandescent light bulb as a rudimentary vacuum tube -- they periodically die for no apparent reason.

[Gris]

Maybe you a bias-modulated jewel? LOL

[My Guitar Weeps]

That's pretty funny...

I just wanted to disclose everything the amp had been through (a.k.a. I had touched or tinkered with) over the last few days before I received any "Well is it screwed in all the way" & "Did you have it plugged in real good" comments...

I like your sense of humor though Gris

[phantomman]

Jus' don't perform any "R13 adjustments" while working on your amp (or any electronic equipment for that matter).

[steve25]

I would hook up a volt meter set for ac volts across that pilot scoket and make sure that the voltage is steady, you PT may be ready to take a dump!

[My Guitar Weeps]

Out of curiosity, which transformer is the one placed in danger should you run the amp without a speaker load? I can never remember.

[phantomman]

Tha'd be the output transformer, Robert.

Examining the chassis from the rear, it's located approximately in the center, between the reverb choke and the rectangular filter cap can.

HTH

[My Guitar Weeps]

For the record, that's what I thought......but

There is a story behind my question about the transformers.....I figured I'd just go ahead and ask and run the risk of looking very elementary versus confessing to breaking one of THE cardinal amp rules.

Basically steve's answer above about the PT possibly getting ready to take a dive raised the hairs on the back of my neck. You see amidst my search to refine the voice of my used DRRI, a couple of evenings ago I was trying the amp out with different speakers. It's a bit of a pain to remove the chasis, power chord, & tank just to try a new speaker out in the combo when you have 2 or 3 speakers you want to try besides the one in the cabinet. Enter my two 112 ext. cabs and speaker cables.

In my haste, I failed to connect a speaker load to the amp during one of my "Speaker Taste Tests". The amp sat on standby warming up for a good 10 minutes or so without a load and then an additional 3 minutes or so while I checked the volumes on my guitar, the amp, circuit breaker on the instrument cable and everything but the speaker cable trying to figure out why I had NO SOUND.

Eventually I turned to the back of the amp to check the tubes and "Walllla". I couldn't believe that I had made such a stupid mistake. What imbecile turns on a tube amp without a speaker connected I thought. That's such kindergarten amp basics. I love my instruments.........I really love my amplifiers too. I've never been a spoiled rich person. I've worked hard & earned everything I have so I was very dissapointed in myself and feared I had harmed one of my own.....

That's when I cut the amp off...cussed.....waited a few minutes....cussed some more...... ....connected the speaker to the amp and turned it back on. That's when I really started pying attention to every little thing on the amp. Since I'm not a trained electrician or amp tech, I was looking for anything out of the ordinary to see If I had damaged the amp in any way. Several minutes later I'm feeling like the little booger is out of harms way and has weathered the storm like a true soldier..........then jewel light goes on the qwirk. Next morning I'm here on the forum.

No turn on amp with out speaker.
No speaker load on amp make transformer die
No live transformer, No live amp
No working amp make wallet unhappy

Atleast that's the way I have it embeded into my head until I figure out how to work on these amps of mine and somehow come into a stash of replacement transformers...

That's why when Steve said what he did about a possible dead transformer issue, I thought sh_t.

[My Guitar Weeps]

Tha'd be the output transformer, Robert.

Examining the chassis from the rear, it's located approximately in the center, between the reverb choke and the rectangular filter cap can.

HTH

[phantomman]

I doubt -- seriously -- that you've harmed your amp, Steve.

The wonky pilot lamp may be (probably is) jus' a simultaneous random aberration.

[Gris]

Have you done the obvious and changed bulbs?

[phantomman]

Here's a real "this is no sh*t" war story......

A few decades back, my brother (Tom, a bassist) an' me were jammin' at an outdoor kegger party with some other guys we knew.

We were into Mountain an' Tom really liked that "fuzzed out" Felix Pappalardi sound. He was usin' a '68 Showman with D-140s an' for some added "kick", my '67 Bassman head hooked to my Showman 15 cab (tone ring type, single 15-inch EV-SRO).

Well he had that Bassman dimed an' wired to the cab with a guitar cable (hey we were dumb, didn't know squat back then). Anyways, it sounded really good an' we ran through a buncha Montrose, Deep Purple, James Gang, Mott The Hoople, Mountain, etc. All at "concert hall" volume of course.

Midway through "Theme From An Imaginary Western", we smelled what seemed to be burning plastic an' the Bassman began cutting in an' out. But we ignored it an' jus' played on. After we finished we took a look at the Bassman an' discovered that the guitar cable's outer plastic jacket had melted away, along with the insulation for the two conducting wires, ie: it was a dead-f*cking short across the amp's O/T. An' he'd been playin' the amp in that condition for at least five minutes at full power (it wasn't real conspicuous 'cause the Showman was workin' fine).

Bottom line......you can beet a Fender tube amp like a rented mule but it can take some severe abuse before death or serious injury occurs. If there were a W-3443E mil-spec for guitar amps, the Fenders would qualify easily.

[My Guitar Weeps]

Wow.....sounds like an ole' Timex Commercial (Takes a Lickin' & Keeps on Tickin')!!!

I'm sure I tend to play it safe and too precautious...aka paranoid, but that's just the fear of the unknown...
As my knowledge builds about amplifiers, I'll bet that I become more realxed when it comes to little nuances like this. I'll know when a real problem occurs and what else it can affect.

I appreciate the feedback. I need to get some spare bulbs for the parts drawer anyhow. I have 3 amps that use the same jewel light. Don't know if they use the same bulb, but the jewels are interchangable on all of them (03' Orange AD30htc, 02' DRRI, & 71' Traynor YBA-1)

You gotta go to Radio shack to pick up the GE #47bulbs, or can they be had at say the Depot or Wal-mart? I'm sure you can order them on line too.

[Gris]

if you order them snag some colored ones. I put a blue blub under an 'opaque' white jewel and it was the coolest 'smooth aqua' you ever saw... ;-)

[My Guitar Weeps]

Cool