Tube amp build (s)

[JohnH]

Man, it's been awhile since I've been on the forum!

We got hit with lockdown a week after I last posted, and I haven't had a chance to work on any 'for fun' projects since (that home-schooling/wfh combo really hits hard)

I figure the Xmas break is a good time to finish this 18W build (though I realised an order for parts I made in August never turned up, and I didn't notice because life was so chaotic! - they're re-posting it, so hopefully it will be here soon)

[McCreed]

Good to see you back at it John!

[Marcel]

Hey John,

Was admiring your handy work in the pic you posted, and found a point of concern. The tabs on your big electrolytic cap in the photo seem a bit to close for comfort to the chassis. It may be a optical illusion but I thought I'd mention it, particularly as the -ve will be earth but the two +ve terminals will be at something near 400VDC. In my books the greater the distance they can be from the chassis the better. It may be a simple a fix as rotating the cap in its mount until the +ve terminals are as far away from the chassis as attainable.

[Simon Barden]

A good point well made, Marcel.

[Simon Barden]

It's probably worth taking a few more photos of the wiring so far, in case anyone can spot anything else that needs attention whilst it's easy to rectify.

[Simon Barden]

E.g. when soldering the turrets, I'd space out the transformer-end electrolytic cap from the 5W resistor next to it. That resistor will get warm, and electrolytics will dry out faster when warm. Make sure that resistor is well off the board and has as much space around it as possible.

[JohnH]

Good call Marcel, though in this case it's an optical illusion - here's a better pic (I can't space them further from the chassis than this)



Will definitely post build pics as I go. Nothing is soldered on the turret board yet, and the legs of the components haven't been trimmed - I'm just setting them out to make sure the layout works (I'm working from the Valvestorm 18W TMB layout, but have an 18W turret board with slightly different layout, so I'm taking it slow to make sure my adjustments still match the valvestorm schematic)

[JohnH]

It just occurred to me it may not have been an optical illusion, but possibly I took the photo before I tightened everything up!

In any case, suggestions and observations are always welcome; I want to build it as well and as safely as possible!

[Marcel]

Yes, it it hard to know the state of play in any photo unless you are told so all you can do is make an observation...

That last pic looks fine in my books. Keep the blob soldering to a minimum and you should be sweet.

[JohnH]

I just had this super fun parcel arrive in the post (ordered from here).

I only ordered it a week ago, so it came quite quickly. It was a bit of a gamble, as the dimensions on the site don't show the cut out size for the faceplates. Thankfully it looks like it's a perfect fit - I might just need to get faceplates that are 5mm taller than the ones that came with the chassis, but I was going to get new plates anyway so that's not a huge drama.