MOD 102 Kit not powering on at all. Any suggestions?

[sluckey]

Move the red wire...

[Stevem]

Bingo!

[vipor3D]

Move the red wire...

The picture is very helpful! Thank you

[LOUDthud]

That layout won't win any awards for neatness

[vipor3D]

That layout won't win any awards for neatness

I didn't think it was that bad considering this was my first build, and I don't do this kind of thing often.

How/what could I improve for the next build?

[Reeltarded]

I am about to make a joke.

Don't post gut shots.



So, you moved the wire and it rocks now?

[vipor3D]

I am about to make a joke.

Don't post gut shots.



So, you moved the wire and it rocks now?

I guess I was asking for that critique of my gut shot lol

I haven't moved the wire yet. I won't have a new fuse until later today, so I was waiting until then

[Stevem]

It does not look too bad for the guys first build, besides it's only got two gain stages before the output so other then a phase issue with the OT you would probably have to work at getting it to oscillate.

[vipor3D]

It does not look too bad for the guys first build, besides it's only got two gain stages before the output so other then a phase issue with the OT you would probably have to work at getting it to oscillate.

Thanks. I have a couple questions regarding the fuse/switch wiring hopefully you (or others) can answer. It was mentioned on another forum that the wiring suggested in this kit isn't really correct by modern standards.

The kit says to wire the black PT strait to the fuse and white PT to the switch with the neutral AC also going to the switch. The modern wiring that was suggested instead had a wire from the outer fuse lug to the switch, black PT to the other side of the switch and then solder together the neutral AC with the white PT wire.

Just wondering if this is accurate? If so, is the benefit that it essentially adds the switch into the hot line?

[ViperDoc]

When using a single pole switch as in your build, wire the AC hot directly to the fuse and then to the switch, connecting the PT primary hot to the other side of that switch. Connect the AC neutral directly to the PT primary 0V lead.

When using a double pole switch, connect the AC line as above and the neutral AC and 0V PT primary to the second pole of the switch so that both AC Hot and Neutral wires become disconnected when the switch is open.

[Phil_S]

Do what ViperDoc says. The fuse is there to protect your house from a fire. short, or overload condition. While it may also protect the amp, that is not it's primary purpose. For that reason, you want the hot wire from the wall socket to go directly to the fuse. IOW, as soon as you plug in, whether the switch is open or closed, the fuse is in the a/c circuit doing it's job.

[vipor3D]

I am about to make a joke.

Don't post gut shots.



So, you moved the wire and it rocks now?

Update: Moved the wire to the correct terminal lug and put in a new fuse. I tried powering it on again but it instantly lit up the bulb limiter

[Stevem]

Yes the bulb will glow bright for a few seconds since the tube filiments are pulling a lot of current as they warm up, but then the bulbs glow will reduce as it idles until you play Thru the amp.

[LOUDthud]

I didn't think it was that bad considering this was my first build, and I don't do this kind of thing often.

How/what could I improve for the next build?

I didn't mean to denigrate your workmanship, my comment was just about the use of terminal strips and their somewhat random placement and spacing of components. (Even their effects pedals are built on terminal strips.) If you look at some of the Tweed Champ and Tweed Princeton builds posted here, they look much better with an eyelet board even though the circuit is quite similar. Much easier for the novice builder to spot mistakes and components are not so crammed together.

For your next build, choose a kit that has an eyelet board and practice striping wires to lay neatly. You may need to purchase some extra wire. Be extra careful when you strip the transformer wires, it's kind of messy if you cut them too short.

Note: On a push pull amp, it is sometimes necessary to reverse the wires from the Output Transformer to the Plates of the output tubes. Leave the wires full length until the amp is running properly.

[vipor3D]

Yes the bulb will glow bright for a few seconds since the tube filiments are pulling a lot of current as they warm up, but then the bulbs glow will reduce as it idles until you play Thru the amp.

Well I tried it again with the half amp fuse as suggested and the bulb lit up. However, the pilot light on the amp did not. For a brief second I heard a slight hum/buzz come through the speaker then the fuse blew and the limiter bulb went out.