18Watt.com

Before I heat up the Hakko, would greatly appreciate a second or third set of critical eyes on my board design for this 36W build. Is anything on this asinine? I haven't drawn up a schem or a complete layout yet, but it's adapted from the Ceriatone layout. Again, fantastic board prepared for me by Doug Hoffman, cost was $25 and arrived in 30 hours from when I submitted my DIYLC file into Doug's system.
Thanks in advance!

Without diving deep into it, the thing that stands out the most is that the preamp filter caps are arbitrarily placed. Whenever possible, they should be directly next to a given stage's cathode cap. Making that adjustment will also make the turret layout easier/cleaner.

It looked funny to me at first also, this is basically the ceriatone board sequence. It's actually very similar to Richie's 36 Watt TMB Layout v.2.0 so I figured I'd give it a try.

JMPGuitars wrote: ↑

Mon 06/08/20 6:18 pm

Whenever possible, they should be directly next to a given stage's cathode cap.

I think you meant "coupling cap". That is exactly where they are.

crgfrench wrote: ↑

Wed 06/10/20 1:53 am

JMPGuitars wrote: ↑

Mon 06/08/20 6:18 pm

Whenever possible, they should be directly next to a given stage's cathode cap.

I think you meant "coupling cap". That is exactly where they are.

No, I meant what I said. A stage's filter/decoupling cap should be next to its cathode cap.

Why would that be? I would think it should be near the anode rather than the cathode -- from a schematic viewpoint?

crgfrench wrote: ↑

Wed 06/10/20 3:11 pm

Why would that be? I would think it should be near the anode rather than the cathode -- from a schematic viewpoint?

It's not a schematic thing. I don't remember the reasoning, but maybe when Zaphod_Phil is less busy with work he can explain it. I think he told me why a while ago, but I forget.

Picked up a 2x12 cabinet loaded with WGS green berets today for $200!

Wow!!! Some people have all the luck!

crgfrench wrote: ↑

Wed 06/10/20 6:22 pm

Picked up a 2x12 cabinet loaded with WGS green berets today for $200!
20200610_191550.jpg20200610_191640.jpg

Going back to the " hauling gear period"... that's gonna be a heavy piece of equipment

I'm installing this board into a 1x12 cab, with a Ceriatone 36W chassis and Heyboer iron from GDS. I posted these pics in another thread but they probably really belong here since this is where I'll post updates of this build. The GDS PT has a smaller footprint than the Ceriatone PT so I made this adapter.
The corners of the PT opening need to also be filed or drilled slightly for this, as you can see in the images.

Board soldered, all except the ground bus.

crgfrench wrote: ↑

Fri 06/19/20 8:11 pm

Board soldered, all except the ground bus.
20200619_205726.jpg

Looking nice Craig!!!
Watch out to not overheat the caps and resistors when you attach the ground buss. That takes more heat and time wit the soldering tip, so it's hard to not overheat other components.
I'm also educated connecting the components laterally on the turrets instead of in the top hole. That way there is a better mechanical connection in case solder would come loose.

Looks great!

Thanks guys. I always use a heat sink clip when soldering every cap lead. Takes a bit more time but I like the security.

Bieworm wrote: ↑

Sat 06/20/20 4:33 am

"...connecting the components laterally on the turrets instead of in the top hole. That way there is a better mechanical connection in case solder would come loose."

I prefer mounting them in the top hole, it's the most solid connection. It also facilitates later mods or repairs down the road. Doug Hoffman recommends this method, see
https://el34world.com/boardmaker/BOARD3.htm
Also, if it's good enough for Danny Russell, it's good enough for me, see http://www.bletchleyamps.com/www.bletch ... oduct.html
OTOH, Mark Bartel wraps them your way and his amps are awesome too.
Bottom line, either method is fine if you solder properly.

crgfrench wrote: ↑

Sat 06/20/20 9:42 pm

Bieworm wrote: ↑

Sat 06/20/20 4:33 am

"...connecting the components laterally on the turrets instead of in the top hole. That way there is a better mechanical connection in case solder would come loose."

I prefer mounting them in the top hole, it's the most solid connection. It also facilitates later mods or repairs down the road. Doug Hoffman recommends this method, see
https://el34world.com/boardmaker/BOARD3.htm
Also, if it's good enough for Danny Russell, it's good enough for me, see http://www.bletchleyamps.com/www.bletch ... oduct.html
OTOH, Mark Bartel wraps them your way and his amps are awesome too.
Bottom line, either method is fine if you solder properly.

You're right

Either method can be fine (if you're skilled), but the external j-hook is absolutely superior. Besides the fact that the j-hook gives you a solid mechanical connection that top mounting doesn't, not all turrets heat evenly throughout (inconsistent plating, etc..), so you can get potential cold/poor joints that you can't see. In other words, top mounting does NOT give the most solid connection, not even close.

For a well experienced technician with very good soldering skills, and 100% perfect turrets, it's maybe not a big deal. But for the average DIYer, it can be a huge difference, especially in the real world were turrets aren't always as consistent as we'd like.

Thanks,
Josh

Side note: neither methods facilitates modification better than the other if you don't have the right tools. I have a good desoldering gun, so it makes no difference to me.

If you're top mounting your components without an adequate desoldering gun, then it's possible you're not removing all the solder from the turret when making changes. A less-experienced DIYer will likely drip solder through the bottom of the turret (I've seen this - like a solder stalactite).

On the other hand, if you're externally mounting your components, you can more easily remove solder with the common tedious methods like desolding braid or spring pumps.

Obviously Craig's skills are higher than the typical DIYer, but since the two of you won't be the only people reading this thread, it's important to point these things out.

Thanks,
Josh

Speaking of J hook method, I have 3 under-board solid wires on this build (the last B+ run and a couple others); I run them up all the way through and j hook them over the top. I was fortunate to have been a professional TIG welder when I was younger which helps with soldering generally, and the non-eutectic nature of 60/40 in particular.