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Hello Trinity Forum:

My name is Muddy and I am a hopeless tone junkie and first time amp builder. Inspired by the Tweed Deluxe sounds of Niel Young, Mike Campbell (Heartbreakers), Don Felder (Eagles) and others I am attempting my first amp kit. This is the start of a new build thread I intend to post some pics of the project thru development. I know I will have some questions and am asking for help from the Trinity community. Thanks in advance to all of those who would like to help me with my journey to tonedom.

I admit to a minimal knowledge of electronics although I do own tube Hifi amplifiers that I use in my home stereo set up. To warm up to this new hobby I started by building a Stomp box which helped me practice my soldering. I also created a lab with essential tools where I can perform this work.

To test the image upload here is my first pic of the progress so far;
1) Hardware jewelry installed and some wiring started.
2) Cabinet drilled and Speaker readied.

Next is the heater wiring I believe.....

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Muddy
Calgary,AB

Oh yeah! And you got a tone tubby too!!

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

Well it didn't take long to have a question about heater wiring...Excuse my ignorance but I don't seem understand how V1 get the power passed to it? Unlike the power tubes where the wire runs from pin to pin on the preamp this it looks like a different route to me.

Is the wire bifurcated (split) so that it goes to both preamp tubes? Or are there two separate pairs of wire from the V3 tube to both preamp tubes?

Please chime in if you can help, thanks.

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Muddy
Calgary,AB

Daisy chain the wires from the power tubes to preamp tube heaters. Keep the polarity consistent from tube to tube, I.e. keep pins 4-5 connected on both tubes with the same wire. Same for pins 9. Review the layout.

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

I guess I don't know what daisy chain topology is, I admit to being out of league with wiring. Does this mean that there is 2 sets of wire (Red+ and black-) running out from V3 to each of the preamp tubes?

Explicitly this would mean from V3 Pin 2 has two red wires from it; one goes to V2 Pin 9 and the second red wire goes to V1 pin 9.

Likewise there is two wires from V3 pin 7 (black) that travels to V2 Pins 4 and 5 as well as a second wire travels to from V3 pin 7 that travel to V3 Pins 4 and 5

There are also jumpers from Pin 4 and 5 for each pre-amp config.

Let me know if this correct, thanks. Maybe I am reading the diagram too literally? I don't see two sets of wire just one.

Thanks.

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Muddy
Calgary,AB

run the wires from tube to tube. aka serial.

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

Thanks; I think I've got it now. Please comment on the images if I have screwed this up.

1) Heater wires complete; V2 gets juice from V3 pin7 (negative) and pin 2 (positive). V1 gets (negative) from V2 pin 2 and (positive) from Pin 9. Pins 4and 5 are jumped. Nothing soldered please let me know if I have this right!
2) Jumpers mounted not soldered.
3) special coax wire prepared not installed.

I found the actual placing of the wires somewhat finicky; difficulty ID-ing the right pin. Ok now time for scotch.

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Muddy
Calgary,AB

Jumpers aren't correct. Compare it to the attached pic.
I think the heaters are ok.v4 gets power from the light socket, v3 from v4 etc. There is no positive or negative in the heater voltage btw. It is AC volts.

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

Yeah thanks Stephen; I had thought the two long leads were jumpers but when in fact they feed the power tubes V4 and V3 to pin 6. From the diagram it would appear the two leads don't make an appearance on the top side of the board and poke out from underneath near the 6V6 sockets.

Here is a pic of dry mounted board and now I will heat up the old iron....

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Muddy
Calgary,AB

That last image has a mistake with a resistor on the dry mount. Can you find it?

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Muddy
Calgary,AB

hard to see in the shadow, but it looked OK. Which one?

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

It is a good thing I am taking my time with this; double/triple checking so far it working to find errors; thanks for the tips and help.

The 4K7 and 22K ceramic resistors were in the wrong position. Luckily I had not soldered anything.

Here is the board on the last day of the year; good steady progress. Will install trannies next and solder heater wires.

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Muddy
Calgary,AB

The resistors look like they are still in the same position (the right position).

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http://pdfelectronics.com

Kurt: yes I may have confused myself, the photos do look similar but are now correctly positioned; I think I took the ceramic resistors out to bend the wires so there was more room for soldering as they are tight between the caps. At that time I then put them in backwards.

My New Years progress to date:

Board is ready
Power transformer is installed (although I have a question)
Recto socket is wired

Power Main: I struggled with the strain relief thingie; do I need a tool to compress it? Any suggestions appreciated.

Question: If I am following the diagram both the black/white wire and the black/red wire connect to the live part of the power switch because they get the power from the main?

Question 2: There is no special order for the Yellow transformer lead to the recto socket. As in it doesn't matter which yellow lead is connected to pins 9 (B+) or pin 2. If this correct then why?

Photo of my Recto wiring. THX in advance for any help.

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Muddy
Calgary,AB

Strain Relief help - viewtopic.php?f=12&t=1296

The Black/white wire and the black/red wire connect to the SWITCHED part of the power switch because they are connected in series for 117V mains.

There is no special order for the Yellow transformer lead to the recto socket. It doesn't matter which yellow lead is connected to pins 8 (B+) or pin 2 because it is AC voltage and AC has no polarity.

Need to see the "keyway" in the tube socket to confirm it is wired correctly.

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

Thanks Coco for the helping me understand the circuit better; afterall it is the journey not destination that is important. The strain relief was a PITA but the main power work looks good and is now somewhat understood.

Sunday AM update:

Thing are really converging as now the transformers are in place and board is installed in the chassis. Next step is soldering the jack and pot leads to the board and doing the rest of the tube socket hookup. As you can see from today's photo I used little pieces of tape to remind me the destination of the flying leads. Other thing I have learned; I made some of the flying leads too short and had to resolder longer leads to give me more options for trying to separate the signal from heater circuits.

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Muddy
Calgary,AB

I like to heat up the strain relief with a heat gun first before installing it. The plastic becomes a bit more flexible and easy to work with.

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http://pdfelectronics.com

Muddy,

I inspected your hi res pic of your board. There are some suspsect solder joints. I suggest you reheat them all (use enough heat, they look like they are a bit "cold") and fill each eyelet with solder.
you might have some issues with the board with noise & reliability of you dont.

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

Stephen:

Hmm.. could be the lighting some appear shinier than others due to the angle of light. Some solder points on the board had the solder "crater" into the hole so they look different than the joints that "puddled" on top. Perhaps you could tell me which ones are suspect? Thanks.

A had a set back on Sunday as I discovered a mistake in the heater wiring pins for V1 and V2. Pins 9 for both sockets were Ok but where I should have had pins 4-5 I had pins 3-4 by mistake. I think i was thrown off by the diagram as my sockets are orientated 25 degrees different than the diagram. Maybe the diagram could use updating or maybe it is my lack of experience dealing with tube sockets on the business side.

Before I resolder them perhaps a comment on keeping the signal wires out of the way of the heater wires. See my V1 setup.

THX

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Muddy
Calgary,AB

Question: To bench test it without tubes do you use a speaker ? Is that the load the instruction are talking about?

To drain caps: can this be dome with just using the B+ at the power switch to ground?

Thanks in advance.

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Muddy
Calgary,AB