Say hi to my new friend !
It's nice collecting all glowing Tek scopes, but I also would like to find some period accessories to go with them. Cool plugins or some stand alone piece of TE like here.
Makes the collection richer, more interesting, more diverse, and adds features to my scopes, making them more useful / usable, which is cool
So I got lucky and found this little guy ! Love this small TE of the period. Looks just like a glowing Tek, just as cute, yet much smaller, so more manageable !
No, no fast pulser for me, unlike one of our friends recently... but I found this type 1121 ! It's a pre-amp. Amplifies the signal by 100, fixed gain. Has also an attenuator as well but I don't see the logic in attenuating a tiny signal that your are trying to amplify, but it's just me I guess...
I already have my type 502 and 502A which can measure tiny signal, up to 100uV / cm sensitivity. However this comes at the price of a ridiculously low B/W : a few tens of kHz IIRC. The advantage of this pre-amp is that coupled with a "regular" 500 scope, it can achieve similar sensitivity, but while giving you about 15MHz B/W !!! So a lot more useful in practice !
So that's how I justify this purchase. But the only reason really is that it's cute and will be a great addition to keep company to my scope collection. That's all...
I am really lucky I found it, because it should have escaped my radar ! It did not show up with my usual / Daily search terms : "Tektronix", "Oscilloscope", "Metrix"...
BUT I found it anyway because... same guy was selling a piece of Metrix TE that caught my attention, and noticed the guy had no less than 174 other items for sale ! So I though hey may be he has some other cool stuff.... so I spent some time skimming his 174 ads. Turned out 95% of it had nothing to do with electronics at all, but it was worth making the effort to go through all of his ads because yeah he had this cutie for sale as well !!!
Looked decent on the outside, only 50 Euros, willing to ship, and I didn't have to twist his arm to get additional pics to see the interior, and it looked great inside as well (and complete). So I just could not find any good reason NOT to buy it !
This type of Tek TE is ultra rare here, first I see in years of looking for Tek stuff. So knowing it would probably my first and last of this kind, I had to get it, so that I have at least one to play with.
So I just received it this evening. Some piccies below.
Condition :
1) cosmetics : on the outside, rusty screws on the handle bar and bottom cover, easy enough to replace. Inside, really clean, minor amounts of dust. Only thing to report would be a crusty TO3 package transistor. I gave it the usual quick 30 minute clean in the kitchen. I am surprised at how good it came out. Was crusty as hell, but it's amazing what a bit of spit and polish can achieve. UHF connectors and bright work and face plate look very decent now, quite pleasing to look at. Not NIB of course, but for a thing of this age it looks very nice, no show stoppers.
2) Electrical : guy told me there was a gassy tube, as he could see one that had white sutff at its top. Said it was a 6DE7 type tube. Looked it up in the schematics, it's part of the PSU so quite needed... Never heard of this tube model before, none of my numerous Tek scopes have any. Searched ebay, seems fairly common and dirt cheap in the US, but not so over here. In Europe ebay found me on ly 3 Of them ! One in France, NOS/NIB for 20/25 Euros shipped. Another one in Spain, again NOS, same priced. Last one was cheaper but used, and located in some Eastern European country, think it was Lituania or something...
Went for the French one, easier to sue him in case something goes wrong, and the fastest shipping time of all 3 of course, which I wanted.
I received the tube yesterday, just before the pre-amp, great. So I was able to replace that gassy 6DE7 this evening, great.
Pulled the old one... no wonder it's "gassy" : glass is broken ! What's weird is that it broke extremely cleaning, one single piece, no debris, and it's still attached to the bottom of the tube. Strange... it's like someone took a laser cutter and cleanly cut a piece of the glass.. see pic.
Attenuator : it's the dreaded " Turret " style monolithic assembly, that I read about on Tekwiki.... First time I have one... let's hope it works or else it's a lost cause. Luckily since it's a pre-amp, the attenuator is not needed at all for proper operation. It's just there as an extra feature should you want one... so worse case, if it's fucked, it can remain fucked and I can still use this pre-amp just fine
Obviously would be cool if it worked and this TE was fully operational... that goes without saying.
3) Mechanical : that's the main area of work to restore this thing. Needs some work... it clearly got dropped. Its four little plastic feet underneath, got pushed in and bent the front and back panel of the chassis, as well as bending the bottom cover of course... which is easy to see on the pictures as the edge of the cover does not line up at all with the side panels. Not the end of the world to fix, but needs to be done with care and accuracy, with proper tools. Not something I can tackle at the moment, but surely will later.
It powers up. Fan rattles a bit as always, blades need adjusting, routine stuff.
Too late to embark into testing / assessing it properly, plus I want to do it, for the first time, nicely.. with proper coax cables and adapters, not with a shoe string as I have always been doing so far. So as soon as I get my Farnell order which carries coax cables and various adapters, I will be able to play with this pre-amp like a pro
Enough talking, we want piccies !!