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I love the amp..you guys have all been very supportive and its great to be part of the family here, it's nice to feel so welcome...especially joey velour, he's answered all my pms real great guy..

The hard part about helping someone over the interweb is that ,you aren't standing beside them to see up close what is really going on inside your amp..Most people will be reluctant to offer help that may or may not work(or worse, cause more problems for you). I saw your posts on the other forums.(I am GaryE on the other sites)I guess if it was my amp, I would probably just tear it down and start over(but that's just me)Is there someone in yor neck of the woods who will be able to look over your shoulder and help diagnose these issues?I live in Vancouver ,so that would be a problem.I will offer this though, which you may laugh at,if you really can't find someone local with an objective eye , send me the amp, I will go over it for you for if you pay the shipping.I know, who the hell am I? Something to think about.. I am semi retired and spend most of my time working on guitars amps and pedals and have built a bunch of amps from scratch, including a tweed deluxe and brown deluxe clones not to mention a Trinity 18 watter and a Triwatt,so I could help you. Just throwing it out there..

ya know Gary, thats a very generous offer, but i know the great guy on the forum here will get tme going

G-log, awesome offer to be sure.

Ernie, it sounds like you are down to high voltages and some hum. 130V mains is way over spec. Just talked to a Ontario Hydro inspector and if that is the case (measure it again), call your Hydro supplier.

As for hum, the tweed has a steel chassis and can pick up stray magnetics and noise from the environment. That can be a factor. Try it in another room maybe. Also, we included special fibre washers to isolate the input jacks from the chassis . Can you check these are installed and are doing their job? Of course, good separation of heaters from input wires AND the polarity of the twisted wire has to remain the same for the preamp. e.g. red to pin 4-5 on both pre amp tubes, black to 9 on both. As long as they are the same.

And what is the noise like with no guitar plugged in?

After that, we can talk on the phone.

It is hard to follow in the web, so hang in there!

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

played the amp last night and it sounds ok..thanks

Hi Ernie,

Good to hear you have it up and running and it sounds good.

Just FYI, I had pretty high B+ on my 5E3 too, quite similar to yours, though my amp wasn't a Trinity kit so this is just general info (mine uses Deluxe Reverb PT/OT and GZ34 Rectifier). Anyway, I dropped it down to about 360V with a series string of 15volt 5 watt Zeners and put them between the PT Centre tap and ground. My amp sounds great and my tubes are a lot happier now that the idle dissipation is around 13 Watts which is fine for the JJ 6V6's (14watts max) I've been running for the last 12 months.

Here's a pic of the Zeners I set up.


As a matter of interest, have you checked the idle dissipation of the tubes, JJ's are really tough and I've seen them keep going for ages, even over 18watts dissipation!! but NOS 6V6's will probably die a quicker death if you are running very high.

Snowy.

Nice job.
Note that to drop UP TO 40 volts in this amp, you would need 5 watt zener diodes. One 40V 5W zener, 2 - 20's, 4-10's etc. Our B+ is normally 400.

These zener would go between the center tap of the power transformer high voltage winding to the zener diode (anode) then the other side of the zener (cathode) to ground.

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

Sure that sounds like a good plan to put those diodes in there, you guys are such a big help..

Zener Diodes . Not resistors . They go in the Centre tap of the power transformer secondary - the Red-Yellow line.

I calculated the power dissipation to be close to 16 Watts, which is a little hot were you to try some NOS tubes.

So if you feel it is necessary:
Lift the Red-Yellow 0V wire from Power transformer you soldered to the power ground lug on the chassis.
Solder a 20 - 40V 5W zener (cathode towards the ground lug (see picture))
Reattach Red-Yellow line to anode end of Zener.
Slip some shrink tubing over the whole affair.

I'm surprised the B+ didnt go down when the Mains went down from 132 to 122. That is unexplainable.
Worth one more final-final check.

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

my voltages are perfect...trinitys are the greatest along with JV

Hi Ernie,

Here's how to check the tube dissipation if you want to. Just follow the steps through and substitute your numbers for mine, it's really just using Ohms law to figure it out (Current=Voltage/Resistance). When you get to the step about subtracting the screen current, you can just use my figure (3.5ma) and you'll be real close on the final numbers anyway.


I measured the following to start with:
Voltage across Cathode Resistor = 21 volts
Actual Measured Resistance of Cathode Resistor = 250 Ohms
Plate Voltage (Pin3 to Ground) = 357 volts

Then plug the numbers in

Plate Current calculations:
Cathode Resistor Voltage (21 volts) / Cathode Resistor Ohms (250) = 0.084 (84 milliamps)
This is the Cathode Current (including screen current) for BOTH Tubes.
Subtract the screen current (measured to be 3.5ma) = 80.5ma
Divided by 2 (tubes) = 40.25ma Plate Current per tube

Idle Dissipation calculations:
Plate Voltage (357 volts) - Cathode Resistor Voltage (21 volts) = 336 volts
multiplied by Plate Current (.04025 A) = 13.5 watts


Snowy

edit - changed to A from ma - coco

I think you could just solder the Cathode end to the Power Ground lugs on the chassis, and the other end to the PT centre tap and cover it all with the shrink tubing. As per my ptrvious notes .



Rectifier Tube - 5Y3. That would be an interesting test. But 5Y3 REctifier only not old 6V6. In fact, we have always used Sovtek 5Y3 until recently, when we changed to JJ.

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

Snowy -



is actually Amps, not miliamps, so this should read:

multiplied by Plate Current (.04025 A) = 13.5 watts

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

Thanks Stephen,

Yeah I made a typo there, the 40.20 "milliamps" becomes .04025 "Amps" when the decimal point is moved for the purpose of the calculation.

Geez, you'd make a hard core Maths teacher.

Ernie, my opinion is, it's great to go through the excercise of checking dissipation and all that stuff as it's a great way to learn and reinforce understanding of the amp, but seriously, if you think the amp is sounding great and you don't have tubes red-plating or anything like that then go play the heck out of it and enjoy the fruits of you labours.


Snowy

thanks kurtlives....you're an awesome guy..you and JV must be tight cause you're both great guys....always going of your way to help others, the world needs more people like both of you

Is this your first tube amp?

Measure the plate, screen and cathode voltages on the two 6V6's.

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http://pdfelectronics.com

So the Cathode voltage to be measured is pin 8 on both V3 and 4 ???

Yes kurtlives as mentioned twice already, this is my first amp, but stick with me please as I'm making headway !!

Ernie, if you are trying to calculate the dissipation follow my steps, it says measure pin 3 (Plate Voltage), just pick one tube and take the pin 3 measurement, for the purpose of the calculation we are assuming the tubes are reasonably matched, which normally they should be. As described in the calc later you divide by two which gives you the dissipation for a single tube, if they are a reasonable matched pair, they will be close.

Yes, in the previous post I meant Red-plating

My 5E3's run quite hot too, that sounds normal to me, especially after a couple hours playing the chassis is very hot. That's the reason Fender puts those little rubber caps on the switches of the '57 Deluxe, because in some countries the law says they need to take steps to protect people from burning themselves.

Snowy

I have trouble keeping up with all your threads, sorry.

Find the dissipation (above). So yes measure the plate (3) and cathode (4) voltage on a tube. You don't need to measure both because both tube's should have the same voltage. From there go about calculating the plate dissipation (as outlined above).

On my first amp build (SE so ran hot) I thought the tubes can hot too. In reality I didn't have much experience with tube amps and that's just how they are. Tubes run damn hot!
Your amp is probably fine but do some calculations and assure yourself.

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http://pdfelectronics.com

Ernie, we'll all help. I know kurtlives & he is a great help so relax and enjoy. But we all have lots of stuff to do so it may take a while to get back on things. Be patient and happy knowing this help is free!

I did already post hoe to install the Zener. Make sure you establish which end is the cathode and we'll go from there.

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