Types of Caps and Resistors in an SLO

[liam5150]

I want to mod my Jet City 100W head to SLO spec.

I've check throught both schematics and read some threads on here, Harmony Central and the SLO Clone forum.

Although i'm not sure what type of caps to use. Seen bunch of different stuff and from what i gather Orange Drops arent correct to SLO spec.

Also i have seen images of early SLOs that have mostly carbon film resistors and more recent ones using mostly metal films.

Why the change? and any preference?

[Toe-Knee]

in the grand scheme of things it wont make a great deal of difference.

They used to be Mallory PVC & Phillips MKT with Mallory TC filter caps.

Most of the changes were probably due to things going out of production (mallory PVC & the MKTs) or being priced out of the market. The TC caps are now £30-40 each!

There is also the fact that newer parts have better specs & tighter tolerances.

Nowadays they use a mix of vishay & illinois caps in the pre & Panasonic filters. Usually Vishay CCF60 series resistors too. I have seen stock SLO with 716ps in it though also.

I've built a few with various parts including a 1:1 reproduction and i found that mallory150 and vishay mkts sound the closest to the mallorys but there really isnt much in it.

Just go for whats easiest & cheapest to get.

[liam5150]

Cool, thanks!

[MSguitar1]

I use F&T caps out of Germany. My favs in the cap world.

[Zozobra]

I use Panasonic and Nichicon aluminium electrolytic caps for filtering. Their snap-in offerings can't be beat for reservoir and screen filtering. They are cheap, small and offer great ripple characteristics. 25mm cap clamps are easy enough to find if you want to mount them off board. They can be mounted on board with appropriately spaced eyelets and I believe some folks are offering SLO style power supply boards with snap-in sized/spaced pads now.

[Toe-Knee]

I know a guy who makes so I snap in psu pcbs I can hook you up if you like

[Zozobra]

Cool! I may be interested in a few of those. Are they suitable for PT's with no CT? I'm pretty committed to using toroidal transformers with no CT these days as they've so much cheaper and lighter.
I do have a bunch of blank boards I could etch but I've just never gotten around to it.

[Toe-Knee]

He says it could be modded for your needs but it's pretty much the modern slo psu pcb

[Zozobra]

Sweet. I'll let you know. My next amp build after I've finished this preamp I'm working on is probably a single channel nitro which I'm going to build into an AOR I have spare so that will all fit on a turret board anyway.

[Toe-Knee]

These are the boards in question.
The turrets arent on as standard but the solder pads were designed for the keystone ones.