#102 Started. Checking in

[amplifiednation]

With a lot of help gathering parts from many members of TAG (thanks guys) I have started a #102 build. This is my first Dumble build.

At the risk of starting this up and having it smoke I figured I would check in. Even though I think I've got a good idea whats going on, it would be stupid not to do a progress report.

Any help would be greatly appreciated if you see any mistakes.

A couple questions.

-Do different legs of the relays have different voltage output? Does the layout show them jumped in anyway??

-What kind of jack is used for the FET?

-Are the coax runs I did from the relays necessary? I grounded them to the back of the pots. Some of the layouts show coax, some don't.

Thanks in advance!

Taylor

[dcribbs1412]

Looking good so far Taylor
follow the layout and you should be fine...I think Jason's relay boards are a little different...Half way down Tom (Structo)
has a drawing of the relay differences..might want to use a longer screw for relays and use another nut under boards to get them up off the chassis a little
relay thread
https://tubeamparchive.com/viewtopic.ph ... lay+layout
I think most builds used coax to relays
thread for fet info
https://tubeamparchive.com/viewtopic.ph ... t=fet+jack
keep us posted

Darin

[M Fowler]

Taylor looking good. Where did you find the white coax?

Mark

[ToneMerc]

Taylor, here's a common gotcha lately. The AGB universal relays are not pinned/laid out the same as the Dumble relay in the layouts. You will find this out when the PAB doesn't appear to work correctly. I leave the PAB switch on the rear, using an On/On for the R/J which is wired as depicted in the layout for #183.


Here's how I wire mine.

1. Move yel to 1st terminal.

2. Move grn from r/j to 2nd position.

3. Move blu from r/j to the 3rd position

4. The red from 4th term to the treb 1 leg is good.

I generally only use 5 strands (1 on OD) of coax, but you can use 6 runs. You might like the added capacitance.

TM

[alvarezh]

Looking good Taylor.

Darin suggested longer screws for the relay boards, have them long enough to include space for a star washer underneath the nuts. Use them everywhere!

Cheers.

[amplifiednation]

TM,
I made the changes you recommended. I knew there was something to the relays I wasn't getting.

Any changes to the OD relay that I should make? I'll probably leave the coax in there for now...it's easy enough to leave in and see how it sounds.

Thanks for the help. I know the layouts are like 98% there but still there is so much going on in these amps it's good to have some more eyes in there. Also there's a lot to learn from pics from a lot of the build photos, some shortcuts that aren't found in the layouts.

TC.

Here's my rewired relay. added another 22.1m resistor too, again wasn't in the layout.

[ToneMerc]

You have to reconfig the jumper on the r/J switch and then it will match the way #183 is wired using the agb relay. I think attaching both 22M's on the PAB relay makes it easier wiring, maybe that's why HAD started doing it that way.

I'm sorry, I should have advised you on using those backers. I only use them on PAB relay. I sent you two in case you wanted stack them for additional board height off the chassis floor. I use either .375 or .500 standoffs on the OD relay.




Good job, you are knocking it out.

TM

[Structo]

Looking good.

I wished I had went with the precision power supply but I had to keep costs down.

The coax runs most feel are partial to the sound of the amp is all four leads from the Overdrive pots are shielded.

Some run one from the Master pot but if you are careful with lead dress you don't have to use it there.

The FET jack is the Kobiconn 161-0084-E
I just checked Mouser which is where I got mine and they say they are out.
End of life.
You can use a Switchcraft 14b but I tried one and had problems with the switching on it.

The Kobi type jack is much better.

The other jack that can be used is the Calrad 30-385
It is supposedly better quality than the Kobi.

http://www.arcade-electronics.com/detail.aspx?ID=18252

[amplifiednation]

Thanks Tom.

I lifted the OD relay up .5". Looks good that way!

I have my board all ready to go, all perimeter wiring is competed for the most part. Boards should be all populated tomorrow and I will really get down to business.

This is an epic build!

[passfan]

That chassis looks solid. Where did you get it ? I am saving up parts for a dumble build right now myself.

[amplifiednation]

Its a ce chassis. The silver ones are hard to come by

[ToneMerc]

Taylor looking good. Where did you find the white coax?

Mark

Mark, it was donated . I got from eBay sometime back, it's RG-188.

TM

[M Fowler]

My chassis and your coax, a team effort here huh

Mark

[amplifiednation]

Haha yeah thanks to you guys I haven't had to buy many parts for this bad boy myself!

[Structo]

Oh you got a silver chassis eh?

Those are sharp looking.

I want to build a 2nd Gen amp in one of those.