Maximum Volume on startup

Posted by: tanstaafl.

Maximum Volume on startup - 05/07/2015 00:03

I remember that many years ago (like about 13 or 14) there was a problem subsequently addressed in firmware that on occasion caused the empeg to start playing at maximum volume upon startup.

My wife is currently in Alaska, and this has happened to her twice now to the point where she is afraid to use the empeg.

The only thing I can think of is that until yesterday she had a problem where she could not disable the car alarm (she left the alarm remote keyfob here in Mexico) so she had someone clip one of the wires to the siren. The car would work, but the emergency flashers kept flashing, 24 hours a day. Could this have somehow triggered the maximum volume behavior?

Yesterday she got a local stereo shop to completely disable the whole alarm system, and hopefully there will be no recurrence.

tanstaafl.
Posted by: tfabris

Re: Maximum Volume on startup - 05/07/2015 01:41

If the empeg plays at maximum volume upon startup, it is a hardware problem rather than a software problem. The empeg thinks it's in Home mode, as if an AC adapter were plugged into it. A faulty leaf switch in the AC adapter barrel jack is the cause.

http://www.riocar.org/modules.php?op=mod...mp;faqent=87#87

http://www.riocar.org/modules.php?op=mod...;faqent=268#268
Posted by: tfabris

Re: Maximum Volume on startup - 05/07/2015 01:44

And reading those FAQ entries, there is a chance that the wiring work they did on the car might indeed have caused a similar problem, the FAQ says it's possible that either a diode or transistor has blown because of incorrect voltage applied to one of the DC inputs. Anyway, check the FAQ entries. Diagnosis and work-arounds are in there.
Posted by: tanstaafl.

Re: Maximum Volume on startup - 16/08/2015 20:07

Originally Posted By: tfabris
Diagnosis and work-arounds are in there.
It is the AC leaf switch thing. I set Hijack to force DC on bootup, and that has solved the problem for the time being.

Since my brother-in-law has now moved down to Mexico with us, we won't be returning to Alaska any time soon, so I have sold the beloved ShoWagon to a friend in Fairbanks who will take good care of it and of the stereo. (Asking price: $1.00, paid in cash.) He has considerable electronics training and experience, and he will be able to replace that jack.

tanstaafl.
Posted by: aksnowbiker

Re: Maximum Volume on startup - 08/09/2015 18:06

Some follow-up:

It appears that all the plugging and unplugging of the coaxial connector moved the switch contacts around enough to clean them of oxidation, and it works correctly.

I think the contacts could even be cleaned with some dental tools if need be -- reach into the coaxial jack with a slender, pointy thing and lightly scrape the contact clean.

The ShoWagon rides tonight!
Posted by: tfabris

Re: Maximum Volume on startup - 09/09/2015 17:33

Quote:
It appears that all the plugging and unplugging of the coaxial connector moved the switch contacts around enough to clean them of oxidation, and it works correctly.


That state will only be temporary, I'm afraid. Problem will return randomly until you replace the jack.

Quote:
I think the contacts could even be cleaned with some dental tools if need be -- reach into the coaxial jack with a slender, pointy thing and lightly scrape the contact clean.


If I recall correctly, the contact in question, the one that senses whether the AC Adapter is plugged in or not, isn't reachable from the outside.

You could clean the + pin and the - ground tab, i.e., the main power contacts. But these are not the things which cause the problem. The inner contact, the one which changes state when the barrel connector gets plugged in, is not even visible from the outside as far as I know. It's an inner contact driven by lever action from the pushing down of the - ground tab from the outside. I tried searching for a picture or diagram on the internet, but I can't find a good one.

Even if it were visible, though, the job would be so painstaking that I'd much rather just replace the connector with a good one, since it's a very common part and easy to obtain.

In my case, the replacement part has been much more reliable than the original part. My original part failed very quickly in the player's lifespan, and I replaced it with one from Digi-Key, and that one has lasted for many years without exhibiting the symptom. So it's a question of parts quality in this case, I think.
Posted by: aksnowbiker

Re: Maximum Volume on startup - 10/09/2015 06:12

Yow! Too right! I just blasted by full volume Steve Morse. So, I'll get the part from Digi-Key (I see that the original part number is discontinued, but they offer a functional equivalent - Digi-Key part number SC1313-ND).

Are there any other bits from Digi-Key that I should perhaps have on hand?

Thanks!
Tom
Posted by: mlord

Re: Maximum Volume on startup - 10/09/2015 11:52

Yeah, hunt down a few of the surface mount fuses for the empeg, just in case you blow one (really, REALLY, easy to do when plugging/unplugging the display cable).

Also get some rotary controllers, for when the rotary knob on the empeg eventually suffers deterioration and begins to behave erratically.

Part numbers for all of these things are elsewhere here, somewhere.. smile
Posted by: robricc

Re: Maximum Volume on startup - 10/09/2015 18:15

Originally Posted By: mlord
Also get some rotary controllers, for when the rotary knob on the empeg eventually suffers deterioration and begins to behave erratically.

It looks like we're talking about a MkII here. The good news is Hugo gave me over a hundred MkII rotary encoders about a decade ago. The bad news is that I still have most of them!

PM me your address, and I'll send you a few in the mail.
Posted by: tfabris

Re: Maximum Volume on startup - 10/09/2015 22:03

In some case the encoder has been replaced with the other type. That's the way it is on my player: I've got a Mk2 unit with a MK2 display board, but an MK2a encoder with the keyed shaft.

Doug, do you know if the encoder on that unit is the keyed shaft type or the round shaft type?
Posted by: tfabris

Re: Maximum Volume on startup - 10/09/2015 22:04

Originally Posted By: aksnowbiker
Yow! Too right! I just blasted by full volume Steve Morse.


Not necessarily a bad thing. Which piece?
Posted by: tanstaafl.

Re: Maximum Volume on startup - 10/09/2015 23:23

Originally Posted By: tfabris
Doug, do you know if the encoder on that unit is the keyed shaft type or the round shaft type?
Sorry, no idea. I bought the player from the brother of somebody who posts on the bbs, and I don't even remember who it was.

tanstaafl.
Posted by: aksnowbiker

Re: Maximum Volume on startup - 11/09/2015 09:07

This one has a round shaft, I think. Hang on. Yep, round. Oh, and the very loud song was Third Power by S. Morse, at about 3:40 or so. Good stuff. I suspect that you introduced Steve Morse to Doug. I think that my contribution to Doug's listening enjoyment was "Weenie in a Bottle" by Weird Al. I stray off topic...
Posted by: canuckInOR

Re: Maximum Volume on startup - 11/09/2015 16:32

Originally Posted By: aksnowbiker
I stray off topic...

That's when the best threads tend to happen. smile
Posted by: tfabris

Re: Maximum Volume on startup - 11/09/2015 20:44

Ah, yes, nice one. I love that album particularly. I like how the guitar solo in the middle goes for the classical guitar instead of the electric. Steve is just amazing.

If you're into amazing guitarists, check out Trevor Rabin's 2012 album "Jacaranda" which has been giving me a lot of pleasure lately.
Posted by: aksnowbiker

Re: Maximum Volume on startup - 16/09/2015 09:54

Originally Posted By: robricc


PM me your address, and I'll send you a few in the mail.


Wow, you sure did! I can now supply four (count 'em, four) empegs with new rotary encoders.

Let me know if there's anything that I can help you out with, Rob.

Thanks again. Will post when the coaxial power jacks get in and I replace with a good one.

Tom
Posted by: aksnowbiker

Re: Maximum Volume on startup - 21/09/2015 09:25

Time for the awesome update:

The parts came (all I needed was the power jack, but I got fuses as well, plus Rob sent me a handful of encoders), and I put the new power jack in there, and all appears to be well. We'll see if it tries to chase me out of the car next time I get in there. If it does, that would speak to some car electrical problems. In fact, earlier today I tried to use the emergency flashers (while picking up Equinox Marathon course markers) and they didn't work at all. Something to look into...

Trevor Rabin -- interesting name. There's a couple of T. Rabin tracks on the player, that Tony no doubt had something to do with.
Posted by: tanstaafl.

Re: Maximum Volume on startup - 21/09/2015 14:51

Originally Posted By: aksnowbiker
In fact, earlier today I tried to use the emergency flashers (while picking up Equinox Marathon course markers) and they didn't work at all. Something to look into...
There is an intermittent short in the big turn signal/windshield wiper/whatever switch (you know, the one that doesn't cancel the turn signal after a left turn) that blows the turn signal etc. fuse. That's why there is a replacement assembly in that box of spare parts I left you. I think it is a relatively straightforward job to replace it, I just didn't have the time or tools to swap it out in the brief time I was in Alaska this summer.

Also, you should look into re-enabling the alarm/auto-start system that the stereo shop in Anchorage disconnected when Jean misplaced the remote key fob. I found the spare remote as well, I'll mail it to you, and you'll have both sets.

tanstaafl.
Posted by: tfabris

Re: Maximum Volume on startup - 21/09/2015 20:40

Originally Posted By: aksnowbiker
Trevor Rabin -- interesting name. There's a couple of T. Rabin tracks on the player, that Tony no doubt had something to do with.


He's originally from South Africa, though I believe he's an official US citizen now. When Yes was re-forming during their mid-career shakeup in the early 80's, he was Steve Howe's replacement. He took the band in some interesting new directions, and wrote a lot of the music that we associate with Yes today. For instance, "Owner of a Lonely Heart" was something he brought to the band. I really enjoy both his solo work, and his work with Yes. His style and technique are amazing, and he's a great composer. He's among my all-time favorite guitarists.
Posted by: aksnowbiker

Re: Maximum Volume on startup - 22/09/2015 08:32

So, I've been sitting and thinking about your last few words: "all-time favorite guitarists". I think about all the fabulous guitar players in my library, and I have to say that David Gilmour is my guy.

For me, he conveys a lot of meaning with the least amount of effort possible. Instead of the mad scramble to play as many notes in the shortest time, he'll play just the right notes and the effect is equally dizzying.

This is not to detract from Mr. Rabin. I will most certainly own an album or two of his in the near future.
Posted by: tfabris

Re: Maximum Volume on startup - 22/09/2015 14:41

Gilmour is also one of my all time favorite guitarists for the same reasons. smile
Posted by: aksnowbiker

Re: Maximum Volume on startup - 26/09/2015 23:47

Originally Posted By: aksnowbiker
It appears that all the plugging and unplugging of the coaxial connector moved the switch contacts around enough to clean them of oxidation, and it works correctly.

I think the contacts could even be cleaned with some dental tools if need be -- reach into the coaxial jack with a slender, pointy thing and lightly scrape the contact clean.


So, after replacing the power jack and letting the old one sit around on the bench for a few days, I just picked it up and started tinkering with it.

It is fairly easy to clean the contact surfaces that constitute the switch -- they are visible, and can be accessed with a slender tool. However, Tony is exactly right -- the trouble is a faulty leaf switch. It isn't a case of dirty contacts (that was what I surmised), it is a lack of spring tension in the leaf contact.

Putting an ohmmeter across the switch lugs, with nothing plugged in, I got continuity, as expected. Then, applying the lightest pressure to the leaf, the connection was severed. A new jack requires considerable pressure to break the connection.

I can't imagine how you could bend the leaf up to restore some spring tension. I've tinkered and poked and decided that it really is dead. *toss*
Posted by: mlord

Re: Maximum Volume on startup - 27/09/2015 01:13

Yeah, toss. I normally try my utmost to repair just about everything, but those power jacks are tiny, cheap (eBay: 20 for perhaps $3), and not repairable.

Cheers!
Posted by: aksnowbiker

Re: Maximum Volume on startup - 27/09/2015 19:11

It is fun putting a ridiculous effort into such things.

I suppose that if you were stranded on a desert island and absolutely had no access to a new jack and somehow had access to your tools, you could come up with something. Saw away part of the plastic, and shove some twigs under the leaf contact. That's assuming that there are twigs on this island, of course.

I just dug through the trash, got out the dead jack and nicked away at it with some side cutters, destroying some plastic and freeing the two ground connectors.



Yowza -- need glasses -- ok, it is possible to take it crudely apart and reassemble the thing. Spring tension restored, contacts back in place and the shard of plastic miraculously snapped back into place, it works and requires some force to break the previously weak connection.



What a great way to kill an hour and a half. Doug might recognize the pink background.
Posted by: tanstaafl.

Re: Maximum Volume on startup - 27/09/2015 20:52

Originally Posted By: aksnowbiker
What a great way to kill an hour and a half.
So, from now on, everybody send their failed jacks to Tom for repair.

Originally Posted By: aksnowbiker
Doug might recognize the pink background.

smile

tanstaafl.