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Hey I was hoping someone would be able to give some insight into the problem I'm having with implementing the trinity vrm circuit in my tc15. I actually etched my own board and had the parts available so it looks different but I've carefully matched it up to the schematic and cannot find an error. I hooked it up by replacing the master volume pot with the 1 meg for vrm, I connected the b+ from the standby switch to pin 1 of the pot which subsequently goes to the drain on the MOSFET. The regulated b+ out I attached to the first filter cap (first pin on cap can) and the ground I attracted to the ground side of the cap can. When I turn the amp on with the potentiometer fully clockwise I get a very low voltage on th e regulated out (40v) so that's not right. When I rotated the pot counter clockwise even the slightest amount the speaker outputs a loud buzzing, I have not measured anything like that as it sounds like an imminent self destruction so I turned it off. I'll try to attach a pic, any help would be much appreciated!

Is it grounded?

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yup, the short white wire is the ground which I have connected to the negative side of the filter cap can which in turn is connected to a single star ground point on the chassis.

Is the Zener in correctly?

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yeah, I matched it up to the schematic and the zener is the right way. I'm assuming of course that the end with the stripe is the cathode like a regular diode. yes?

I built an amp (p1ex) from the ax84 website, and put Dana Halls VVR in it.
I had the vvr a bit like you describe - between the standby switch, and the first filter cap.
I also had quite a bit of hum.
I eventually read a post on a forum somewhere, that Dana suggested putting it AFTER the first filter cap.
That fixed the problem!

Zener correct as mentioned. We've implemented this many times right after standby and at first filter cap and it works. You could smooth it out before the VRM with another cap (8uf - 16 uf) as long as it is high enough voltage. Are you getting variable voltages with hum, or when the noise starts, is the voltage way off from what you'd expect?

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yeah, unfortunately I don't think it's just a matter of placement before the filter cap. The variable voltage is way low (40 v) with the pot turned clockwise and when I attempt to turn it the other direction it blasts a full on buzz through the speaker cab at full volume. I'm starting to think it may be a faulty component. What kind of precautions should you take handling the MOSFET and the Zener which are sensitive to static? Is there a method of testing the function of the board outside of the amp?

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http://www.trinityamps.com/phpbb/viewtopic.php?f=12&t=1176

Well, I'm not getting any love out of this thing. Stephen, is the VRM board and parts still $30 for Trinity customers? I just want to get this done right.

Email me and we can work out something.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps