MadModder
The Shop => Electronics & IC Programing => Topic started by: Bluechip on August 21, 2009, 04:46:59 PM
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Hi Troops
Having got bored with my new pastime of spider blinding, decided to see if I could find a circuit for ecll800 valves ( tubes ::) ). Cos I've got two !
Found this ...
http://www.electricstuff.co.uk/loewe.html
Never seen this one before ...
Whatever next ... apparently devised to avoid Tax .. nothing changes ..
Dave BC
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Build a radio then, or two even....
I might have some 2HF's in my stash....but not any 3NF's I don't think....
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Darren
Given up building valve radios, not keen on dangling off 200v+, just realised there's not much chance of getting an output tranny anyway. So, off to the tip with 'em. Dunno if they're OK anyway. Should have kept my Mullard Tester .. If I had the program card for ecll800's. Doubtful.
Dave
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I've got hundreds of output trannies.....literally....just shout if you want anything
BTW, my amp currently uses 1.1Kv HT, but I can crank it up to 5K or so
Scaredycat..... :lol:
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Scaredycat ?
Damn right I am :lol:
Anything above 18V for cmos, I'm out of it. Once got 900V off a Modulator Amp. Not going there again.
L.M.F. ... big time :lol:
Dave
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very interesting tube .......... or should i say valve :scratch:
i used to repair old radios and guitar amps, the radio voltages were no big deal but the guitar amps were scary!!
i worked on a bass amp for a guy and the output tubes were #6550...........i think there were 8 of them and they ran 750 plate volts.
and 750 volts hurts like :zap: well you know.
just some of my ramblings for night.
chuck :wave:
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Hi Dave
Radio Spares
stock a 3.5w multitapped output transformer 210-6475 if you decide to build some thing with
the ecll800 valves , some people have experimented with ht voltages of only 20v to 45v
the picture of the ecll800 reminded me of an early operational valve amplifier
If i remember correctly at one time grundig sold radios as kit to avoid the taxes
the kit was infact a ready made radio without the valves fitted !
John
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Hi John
Long since gone to the tip. I think I took them the next day. As posted, I've no idea if they were OK. Just got a bit nostalgic ...
That Op-Amp looks interesting.
Some stuff I worked on when I first started work had valve Op_Amps, they were ECC81 or 12AT7's rather than ECC82.
Them and the damn great 6080 double triodes .. used to drive differential relays .. I think that's what they were called ..
The ones that are On - Off - On, rather than On - On, as per a normal C/O relay
Days long gone ...
Dave BC
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Dave, the adverts in your link to the Loewe valve showed they could be sent in for repair as long as the glass was intact. Not a service offered by IC manufacturers today. That said, not many modern ICs cost half a week's wages!
Andy
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Hi Andy
Right! Pity they don't fix things like they used to do.
I've got a duff BC108 here could benefit from being rebuilt ... :scratch:
Dave BC
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Hi Dave
the relays rings a bell
I think I,ve seen reference to magneticaly biased relays that have a memory
that have two coils to set and reset them
as an apprentice in the mid 70's i did see the Mullard NORBIT logic moduals
germanium diode / transistor logic constructed on a small pcb and the potted in colour coded epoxy
looked like an overgrown ic
I think am showing my age !!!
if one junction of the bc108 is ok turn it into a photo diode
before Mullard go wise you could remove the black paint of OC71's intsead of buying the expensive OCP71's
John
have now found a picture
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John
Bit difficult to turn a BC108 into a photo anything. In a metal can, at least mine are .. loads of the things anyway, only about 10p each :)
Apprentice in the middle '70's??
Just a sprog :lol: ... I started Jan 9 1960 IIRC ..
07:30 start, allowed 3 mins, otherwise 1/2 hr docked. First rate was 9 1/2d ( no not pence, the old pennies, ie 1/240th of a £ ) hr.
44 1/2 hr week. Sat AM 08:00 to 12:30 was part of the working week.
You young whippersnappers had it EASY .. :lol: :lol:
Dave BC
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Hi Dave
My first wage was £9 10s and I was well off !
I don't think the work prevention job's worths would let you do half the things I did
working on live equipment in a dusty mixing room by week 3 with the sparks
or working with hot wired glass passing near your head , while kneeling on broken glass
apprentices got all the good jobs didn't they
all you have to do with the BC108 is cut the top off
if you like you can use the NASA can opener !
for more search for " tin whiskers in AF116/7 "
John
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Re valves and getting bitten... I was once a g7 ham but used to help a relative out now and again with cb stuff, and he used to use a zetagi bv300 and later a different one I cant remember the name. Only thing was it used to carbon up the changeover relay and the rig would go deaf with time. So I showed him how to clean the contacts and made up a probe with a resistance to bleed it down properly etc. Anyway, he's mid session with some rare station he'd been after for years and it started to go, so he takes off the cover and hits the problem relay with a squirt of contact cleaner while keying up his base mic to open it. His grounded alloy base mic.....
The valve field collapsed up the contact cleaner spray and into him, it took the heart path across his body and down the other arm and the reaction lifted him bodily across the room into a wall behind and melted his glasses frames into a twisted mess. He went the hospital after and was really ill for a few days.
I never knew contact cleaner was conductive, but Id never been dumb enough to find out the hard way.
Its probably the last time I showed someone how to do something to something really dangerous that I didnt trust 1000% to listen...
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I went through a ham radio phase in the late sixties, as a boy, built a few kit recievers and a transmitter, then moved on to bigger and better things, engines and motor bikes, then went through electronics training for the Marine Corps, in the mid seventies, had tube theory, but was told by instructors not to worry about it, we'd never see a tube out "in the fleet". I retired out of the Corps in '97, my last tour as Non-Commissioned Officer in Charge of the same exact electronics shop I had for my first duty station, right here in North Carolina, and when I left, we still had half the six hundred odd systems we maintained for communications and navigations were tube driven, with solid state pre-amps and the like. At the same time, my new techs, checking in to the shop, mostly had never seen a tube and were shocked. Our radar units were up in the three to six thousand volt range for their finals, that didn't so much hurt as laid you out and got you a visit to the hospital, and two or three days bedrest. I hit 1500 volts of dc/rf out of a transponder, and had a small hole blown in my finger, right down to the bone, took about a year to heal, and almost six months to even start healing.
Working with solid state is very nice and much less painful now, I don't need to go back to tubes or valves as you chaps like to call them, over the pond, although they were easier to troubleshoot, and almost impossible to blow up, unlike the touchy little transistors. Tube amplifiers still produce the warmest sound and are much prefered by the "real audiophile", or so I've been told.
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Tube amplifiers still produce the warmest sound and are much prefered by the "real audiophile", or so I've been told.
Heh, indeed, and they also produce the best distortion/overdrive, for an electrical guitar amp, also preferred by many guitarists to transistor fuzz boxes... You´d be amazed at how difficult it is to distort the sound in a specific, "good" way... :loco:
:wave: