how do you route your PT wires?

[wsaraceni]

looking for some advice as to the best way to run my wires here. doing an 18 watt ac30/rocket style amp with an ez81 rectifier. sitting above this wiring will be the filter caps board (z-wreck style layout on that one)

just wondering how you would run the wires here. usually its hard to tell since they are usually under the board in the pictures.

i'll number the questions so it's easier to answer them

1. the power from the socket, this is what i was thinking. black to the power socket (fuse is integrated), black white to the power switch. then i have one wire to run from the other side of the power switch to the other side of the power socket through the pilot light. should this get twisted around both? meaning, if it's a grey wire i use, black and grey get twisted until the black goes through the grommet, from there the black/white and grey get twisted?

2. the twisted red wires, i was thinking i'd go straight up and then a right angle to the ez81 but this will put it parallel to the heaters. any issue there?

3. they yellow and white i'd leave kinda as is, just many the length work better

4. the heaters straight up and then right angle to the first el84 (similar to how it is there, but about 2 inches shorter

5. the red yellow and green yellow go to a grounding point. i was thinking of using one of the existing holes to the left of the grommet in the middle of the chassis.

6. ground the power plug to the open hole right above it

7. ground the filter caps to the 2nd hole to the left of the middle grommet (the one towards the rear of the chassis)

8. need help with the B+ to fuse wiring. the k60 has it nicely twisted but the rectifier is right next to the fuse. i'm thinking of going pin 3 to the standby. standby to the fuse. fuse back to filter cap but twisted back with the wire going to standby. if not twisted, maybe it would be best to tie these together.

[img:764:1024]http://img.photobucket.com/albums/v217/ ... e39100.jpg[/img]

[wsaraceni]

so i decided to just jump in what what made the most sense to me. the 120v was the only part that i was really confused on. this is what i ended up doing.

from the fused portion of the power receptacle i ran a white cable to the power switch, from there i soldered the white/black from the PT as well as another small jumper to the one side of the 120v pilot lamp

from the non-fused portion of the power receptacle i ran a white wire to the other side of the 120v pilot lamp and also ran the black PT lead to the same point.

i left this wire a few inches longer than it needed to be, i hope that doesn't introduce hum. but last time i cut the PT leads to the size i "needed" they were way too short and now i have a PT with leads that are no good.

[wsaraceni]

[img:764:1024]http://img.photobucket.com/albums/v217/ ... adc4a1.jpg[/img]

[img:764:1024]http://img.photobucket.com/albums/v217/ ... 4f5a39.jpg[/img]

here you can see the B+ arrangement all in red. as well as get an idea of the layout of the board

[img:764:1024]http://img.photobucket.com/albums/v217/ ... 03621b.jpg[/img]

thoughts? comments? my last two builds were a mess and i gutted them. this time I'm really taking my time.

[Jana]

Take a look at the thread for my amp build. I'm not saying that is perfect, but it works well for me. I have zero hum in my amps.

I keep the 120 all in a bundle by itself. I don't think that would induce any hum in the 6.3v or the HV AC--those are already AC lines. I keep them separate in case something melts then I don't have the 120 line voltages shorting to anything on the other side of the PT.

I twist the 6.3vac heater wires. I would twist the 5VAC wires if I had those. I don't bother twisting the HV AC. I never put any of these AC wires in the same bundle as anything that is DC or signal. All these wires are on the opposite end of the chassis from the preamp.

[wsaraceni]

thanks. i did look at your build. it looks great. i'm also looking at the guts of my komet 60 as well as tons of pictures of other amps. it seems like the trainwreck chassis are just a little small to do everything nicely. i much prefer the komet style chassis with the laydown transformers. but i think i can make this work.

the hard part i have to figure out now is how to get the heaters cleanly wrapped. no matter what i do, they always seem messier than what i can see of everyone else's. just have to figure that out.

also, do you twist the wires from the choke? they have a pretty long distance to run.

[Jana]

If the choke wires are a long run, I will give them a gentle twist just to keep them together. I will also twist in the CT of the OT primary if it is going along the same path.

Heater wires are always the least *fun* of any wires to run. Just try to keep them away from everything else as much as possible and if you have to cross them, do it at a 90 degree angle with some separation if possible.

[wsaraceni]

thanks. I'm using teflon wire too, which makes it seem impossible to get the heater wires to work correctly. i cannot, for the life of me, figure out how komet does it.

[Structo]

Did you try twisting the heater wires with a drill?

That's how I do it.

Chuck the two wires into the drill, hold the other end with pliers, or have an assistant hold the pliers end. (better)

Turn on the drill, don't go too tight.

I do this with Teflon 20ga and 18ga stranded.

[wsaraceni]

that's what i've been doing. but the part i cant get cleanly is where they connect to the tubes. im trying to cleanly get them to wrap over each other again.

[Structo]

The part where the wire drops down to the tube pins is not that critical.

I have seen builds where they are twisted there but it seems most guys just drop them straight down.

Here is a picture of a #183 clone that HookedOnPhonix built.

I chose this pic because it is an exemplary build and he also takes great photos.

[wsaraceni]

i may try to go like that. i've been using my komet 60 as a build reference.

[img:764:1024]http://img.photobucket.com/albums/v217/ ... fcc4f0.jpg[/img]

and for some reason i can't get it anywhere near that clean looking. i'm waiting for more wire to get in and hopefully i can finish it up nice and clean. i just have a ton of trouble where the red from v2 to v1 wraps over the remaining black from the v2 to v3 connection. pretty much the inch under the coiled shield in this pic

[diagrammatiks]

that komet isn't that great at all.

they might as well not twist the wires at all.

It should look like this...

http://www.aronnelson.com/gallery/main. ... alNumber=2

any info you need can be found in this thread...

http://www.diyaudio.com/forums/tubes-va ... -ugly.html

The whole point is to keep the enclosed loop area small, which isn't being done in the komet.[/img]

[wsaraceni]

isn't that a little overkill though? (and pretty sloppy looking)

i mean the komet is twisted 10x as much as a trainwreck and neither amp have a bunch of hum. i don think i've seen many amps twisted that tight and that close to the tube socket.

[diagrammatiks]

there's actually negligible hum reduction unless you make it to six turns per inch.

I'm not saying that those amps will hum...

I'm just saying that unless you get at least 6 turns per inch and minimize the enclosed loop area between the two wires there's no reason to twist at all.

You can look in Merlin's preamp book in the construction chapter and Morgan Jone's building valve amplifiers for tips on how to do it.

If you want the math behind it the best book is

http://www.amazon.com/Reduction-Techniq ... 0471850683

[wsaraceni]

cool. thanks for the info. ill check it out