[UglyJoe]

Well, that was easy. Funny how the right tool always makes things exponentially easier.


EDIT: This amp is fantastic.

EDIT2: Does it need a headphone load to burn in the caps? I don't see why it would.....

 

[mik000000]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif If you are sure about the other parts, then yes. I can't think of anything else if the parts are correct - unless something has burned out, but that's unlikely at the currents in the relay circuit unless you have something soldered in backwards. The 1N4148 (DM2) should have the numbers printed around its circumference. The zener diode (DM1) does not. Besides checking for whether DM1 and DM2 have been switched, be sure to inspect the orientation on DM1 and whether DM1 and RM1 have been switched with each other. BTW, you seldom can measure resistor values once they're soldered into a circuit - too many things in parallel with them.

I replaced dm1 and dm2 and cm1 for good measure and still nothing. in an earlier post you said there should be 10v+ across dm2 and i have 0v. Does that tell us anything?

 

[Beefy]

Quote:

Originally Posted by UglyJoe /img/forum/go_quote.gif EDIT2: Does it need a headphone load to burn in the caps? I don't see why it would.....

Give up the idea of burning it in. Just listen to it!

 

[UglyJoe]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Give up the idea of burning it in. Just listen to it!

Oh I am... I'm just going to also let it burn in whilst away, see.

 

[tomb]

Quote:

Originally Posted by mik000000 /img/forum/go_quote.gif I replaced dm1 and dm2 and cm1 for good measure and still nothing. in an earlier post you said there should be 10v+ across dm2 and i have 0v. Does that tell us anything?

0V confirms that your relay is not energized. At this point, I'd say that means either QM1 is bad, QM2 is bad, or both. Are you sure that's an MPSA14 you've got in there for QM2? That's the critical part. The BD139 is there to dissipate heat, more or less.

What's the voltage across DM1? Across RM1?

I hate to tell you, but I've got to turn in for the night - I'll take it up in the morning and see if you did anything else.

 

[suneohair]

Can someone tell me what enclosure is used here:

Millett MAX Gallery

 

[mik000000]

The good news is, it does seem that the problem is not with the relay, as I was not looking forward to removing that. The better news is I checked my parts box and I have a spare for both qm1 and qm2.
I have measured the voltages as:
DM1 11.6v
RM1 15v

And unfortunately, I have to head to work to pay for this hobby. Will try again later

 

[MrMajestic2]

Quote:

Originally Posted by suneohair /img/forum/go_quote.gif Can someone tell me what enclosure is used here: Millett MAX Gallery

Its made by ATI in Thailand, dont remember the model. Unfortunetly they are no longer in business.

 

[regal]

Has anyone built a Max with a Amb's discrete power supply? One big advantage of low V tubes is the ability to have an ultra clean power supply for cheap. I always wondered what a tube would sound like with microvolt ripple.

 

[suneohair]

Quote:

Originally Posted by MrMajestic2 /img/forum/go_quote.gif Its made by ATI in Thailand, dont remember the model. Unfortunetly they are no longer in business.

That sucks, I really liked the look of that one. Are there any others that are similar? There is the DigiKey HM903-ND, which is ok. Any recommendations would be awesome!

 

[mik000000]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif 0V confirms that your relay is not energized. At this point, I'd say that means either QM1 is bad, QM2 is bad, or both. Are you sure that's an MPSA14 you've got in there for QM2? That's the critical part. The BD139 is there to dissipate heat, more or less. What's the voltage across DM1? Across RM1? I hate to tell you, but I've got to turn in for the night - I'll take it up in the morning and see if you did anything else.

IT'S ALIVE!!!

It was the BD139. And of course it was the last one i replaced. But it is producing glorious sound now. I need to reassemble it in the chassis and take some time to relax and listen and enjoy.

thanks for the help Tom..as always

 

[tomb]

Quote:

Originally Posted by mik000000 /img/forum/go_quote.gif IT'S ALIVE!!! It was the BD139. And of course it was the last one i replaced. But it is producing glorious sound now. I need to reassemble it in the chassis and take some time to relax and listen and enjoy. thanks for the help Tom..as always

Thanks, but you did the work - I was just sitting here guessing.

The important thing is that you got it working - yay!!

 

[soloz2]

well I received another package today. Sat I got one from Tom and one from Amb. This one was from Brian Donegan

I haven't opened it yet, but I know there's a Darwin, Opus and USB module in there...

Now I just have a few odds and ends to order from Mouser including a push button switch and a few last minute changes as I decided to build a MOSFET MAX.

I also placed an order with Cardas today and added several pairs of RCA jacks

After that I just need to straighten out the whole Parmetal mess (still haven't gotten anywhere...) order a toroid to power everything and a few odds and ends.

 

[amphead]

Congrats mik000000! Another Max Lives

I remember that exact feeling, with the music taking me away as only the Max can. Edit: Stay tuned, the Starving Millett coming to a theatre near you.

 

[sokece]

I'm planning to build MAX this long weekend. I ordered parts from Mouser, Digikey, Beezer and I did not aware that I need to order more for 2N5087 and 2N5088. Basically, I did not order enough 2N5087 or 2N5088.

I read the article from MAX Construction and suggest to match the transistors but the phrase "Matching the JFETs and BJT output transistors has limited usefulness" is unclear to me.

I'm going with BJT route. Is it important to match transistor PNP and NPN? if not what is the side effect?