My Yeti-clone build

[Mr Wright]

I've been mostly lazy this weekend and watched horror movies, but I did get some work done. I fixed the tube sockets the rest of the way and then I mapped out the main board, drilled the turret holes, and started to hammer in the turrets. None of what I drilled out is perfectly lined up, but if anything that shows I'm doing it myself.

That brings us to hiccup #2. Apparently 50 turret lugs was not enough for this build, but no big deal I just order some more and wait a few days.

I'm keeping my tradition of watching sci fi while working, but with the horror twist for Halloween. So far I've watched Event Horizon, Hardware, Leviathan, and a few scifi shows.

Slowly making progress. It gets hard to fit build time in between work time, lady time, and dude time.

[M Fowler]

You'll soon have a whole caddy full of amp parts like the rest of us including an old drill press to set turrets and eyelts.

[Mark]

Here are a couple of links.

http://www.ceriatone.com/images/layoutP ... eti100.jpg

http://www.ceriatone.com/images/layoutP ... hupa50.jpg

These amps do appear remarkably similar.

[Mr Wright]

[img1936]http://i.imgur.com/dVAbJJw.jpg[/img]
[img1936]http://i.imgur.com/slclVsw.jpg[/img]
[img1936]http://i.imgur.com/ba1Vw8p.jpg[/img]
[img1936]http://i.imgur.com/gTc40S2.jpg[/img]
[img1936]http://i.imgur.com/WSTsATY.jpg[/img]

I hope my photo links work. If not I may need some help.

Progress Report!
Board finished.
Chassis fully drilled (I think) and painted.
Transformers bolted on.

Had some ugly soldering around the larger leads for the diodes, the IEC hole was hell to cut, and I scratched the paint a little, but otherwise all goes well.

[mhartman]

Looks great. What did you use to cut the IEC hole?

[Mr Wright]

I drilled a hole and then used a spiral upcut bit on a dremel. The bit kept heating up and deforming the metal. I tried oiling it a little, but it would drip off.

I may just try to use my big router with a small bit and template on the next one.

[xtian]

I find IEC holes pretty easy to cut with a jig saw. Drill pilot holes first, saw cuts aluminum like buttah. Very LOUD buttah.

[M Fowler]

You got a good start now the fun begins building the amp.

[mhartman]

Thanks guys. I always seem to mess my IEC holes up in some way or another. Toughest part of the whole (hole) build.

[xtian]

Here's another tip for IEC connectors: get the kind that attach from the outside of the chassis, so it covers your mess!

[MrHaroldA]

Mr Wright, is it working yet? I've just ordered the last missing components to transform my dull-sounding 1987 turretboard amp into a Yeti, but with a few "touches" here and there.

I don't want to drill any additional holes in my Marshall 1987x chassis, so I want to try to use the jack inputs for switching "era" diodes to ground using the middle lug of 2 stereo jacks, and limit the bright cap switching to 2 options per gain stage using Alpha push/pull DPDT pots.


Still in doubt if I will install the "pussy trim", cause I ain't one

[Mr Wright]

I actually left it alone for a while, and just got back to tinkering since I was off this week.

My PT doesn't have a 5v tap so I decided to forgo the regulated heater supply and just do normal heaters throughout. In order to make sure I have the amperage I needed to switch the indicator light to a mains rated one off of the switches.

I should finish up in the next few days.

I think the girlfriend is upset since this thing has been on my coffee table for months now!

[Reeltarded]

Tell her to stop by my place and check out all the common areas. That will buy you a little table time.

[MrHaroldA]

My PT doesn't have a 5v tap so I decided to forgo the regulated heater supply and just do normal heaters throughout.

I'm leaving the power amp intact from my 1987 build, so my heaters aren't regulated either. I've read that the regulated heaters make the amp "tighter", which I don't want.

I've found a schematic of the Chupacabra somewhere, and I already copied the preamp in gschem:

[img330]http://img.sait.nl/schematics/Ceriatone ... acabra.png[/img]

I'll post the component values for the Yeti and Chupa later on ...

[Mr Wright]

Now I'm wishing I had a pre-existing poweramp.

had my switched wired wrong.
Blew a fuse.
fixed that problem

adjusted my bias up a bit on one tube at it blew. so I pulled it and the opposite tube for now.


If I try to adjusting the bias pots up from min at all I get a huge hum through the speakers. I'm testing bias with my meter on 200mv dc and get .3.


Someone tell me what rookie mistake I am making please?

Also the pilot light would only work in opposite mode. It was on when the amp was off. that was a scary find! I just cut it out.