6B4G - The Resurrection Shuffle

[IslandPink]

I do have a soft spot for Pink of course.

[Cressy Snr]

Knew the inspiration for the colour of my amp chassis had to come from somewhere.
Look at that rear casing.



My gran had the above, 1958 KB Royal Star telly in the 60s when I was very young. There was a cream handle on top if I remember rightly, though it can't be seen in this photo.

It must have been a rental TV as there was a gas meter type slot and turn key thing on the back so it was pay-as-you-go TV.
It took half crowns. She used to let me put the coins in and turn the key. A bloke used to come and empty it.

Apple's Jony Ive is British. Wonder if he too saw this telly when he was a kid. It may have led to his 1997 design for the original Bondi Blue iMac.

[jack]

That really is an astonishing bit of design for the time. Just looked up and it cost GBP 44 in 1958 (the year I was born).

Just under a month's salary for the average worker of the day, or about GBP 940 in today's money.

c.f. http://thedesignlab.co.uk/costofliving2 ... hp?uid=59#

[Nick]

Hmm, normally that would have prompted Apple to sue the original company for stealing their designs

[jack]

Morgan's article on snubbing: http://www.desmith.net/NMdS/Data/Linear ... ctices.pdf

I won't leave it up for long, and please don't re-distribute.

[Nick]

I must admit, intuitively I have never liked the use of snubbers across the diodes, to my eyes they provide a path for HF from the mains into the rest of the amplifier.

[Cressy Snr]

It'll be very interesting seeing what the noise performance is like with these Nick/MJ, snubbing networks.

Anyway I mahaged to get a good afternoon in, fitting all the hardware to the chassis:

[Paul Barker]

pretty, mine will look like a bag of shyte next to that! lol

[Cressy Snr]

Aye, it's a bit pink. strangely enough, it works.

The mains transformer ( centre rear) is rubber mounted, as is the choke at front centre.
The mains and choke are common to both channels and after that, the power supply is doubled up.
Rear filter caps feed each 2A3, then each consecutive filter drops the HT off at each preceding stage.
This arrangement gives the shortest possible power supply route to each stage as each successive filter is adjacent to the valve it is feeding.
Signal path is as short as practically possible.

Amperite Thermal delay relay ( rear left between OPT and mains TX) sits in series with the rectifier heater, giving a 45 second period before the rectifier comes up and the HT begins to rise to the design value.

[Cressy Snr]

Thanks to Steve S for the loan of the Hammond 1627SE.

Didn't intend to build another SET, or any valve amp for that matter, but resistance seems futile and I see no reason for it not to reproduce some very nice music.

It is actually great to get back to what this DIY hobby is all about; simple, effective amps, and simple, effective speakers. Unlike the other complicated stuff, this will be a very quick wiring job in comparison. I like push-pull pentodes, NVA amplifiers and this might be a nice re-introduction to low powered Single Ended DHTs. The OmniMets are certainly efficient enough as they proved when they were connected to Steve's PX25 amp.

It should be soothing with its mellifluous tones by the weekend.

[steve s]

Hope it goes well Steve... it's looks great

[Cressy Snr]

Will hopefully be getting on with wiring up this amp this week.
Never really got going last week, after a terrible throat infection that spread everywhere and developed into a mass of red weals and blisters that covered the palms of my hands and the soles of my feet as well as the inside of my mouth and throat. The pain was dreadful.

Got antibiotics from the Doctor. By early Saturday morning because of the lack of food (I couldn't eat anything solid) I was so weak and confused that Melanie had literally to spoon feed me Ambrosia creamed rice for breakfast. I was completely unable to feed myself, looking at the spoon in front of me and not knowing what I was supposed to do with it; too weak to even speak. TBH it gave me a new perspective on things.
I'm back to rude health now the antibiotics have overcome the infection, but it's not much fun getting older. First it was ulcerative keratitis in my right eye, then Bell's Palsy and now this bastard of an infection. I think I need to start being very careful. The flu jab is essential for me once I've finished these antibiotics.

[pre65]

NIL DESPERANDUM CARBURUNDUM
ILLEGITAMI.

Remain cool, calm and in control at all times.

[jack]

Will hopefully be getting on with wiring up this amp this week.
Never really got going last week, after a terrible throat infection that spread everywhere and developed into a mass of red weals and blisters that covered the palms of my hands and the soles of my feet as well as the inside of my mouth and throat. The pain was dreadful.

That sounds awfully like "Hand Foot & Mouth" - essentially the same thing bovines etc. get. Normally small children get it, but it can be much worse in adults. Interestingly, usually caused by the Coxsackie virus. I kid you not.

If it was that, it's viral, so antibiotics would only stave off any secondary infections, not the main event... anti-inflammatories (NSAID) and pain-killers are your friend.

Nasty & painful - my brother had that really badly many years ago and was put in an isolation hospital.

Hope you're over the worst of it...

[Cressy Snr]

After the doc looked at my hands and shone his torch in my mouth, he did ask if the rash was on my feet too. He did a throat swab and that was sent off for culture.
After that he gave me a hand bell and sent me on my way.

Joking aside it was pretty nasty; very nasty in fact, but I'm well on the mend and the rash is fading daily. It'll probably be a couple of weeks before it's gone completely.