Test Equipment Anonymous (TEA) group therapy thread

[tggzzz]

(SNIP)

In other news, yesterday's GAS was yet another 465, this one with intact feet, two nibs on the cover, and it basically works. OK, some of CH1's ranges are peaky/touchy, and the trigger only works for >0.5 divisions, and some pots are scratchy, but with luck those should be fixable...

Famous last words... 

mnem
Best of luck, brother. See you on the other side.

For once it was better than I expected...

The LT power supplies were OK, and all had <500uV ripple.

The motor works fine.

Found scratchy pot couldn't b cracked open for some fader lube - but it didn't matter since rotating it a few times made it acceptable again.

I expected the twitchy/peaky CH1 deflection to be an attenuator problem. After cleaning the attenuator switches (an easyjob with IPA and a piece of paper), I noticed the problem appeared/disappeared when I attached/moved the input cable. So I heated all the flying solder joints between the input BNC connector and the attenuator board, and so far it is rock solid.

The trigger was, as I hoped, simply a case of tweaking the trimpots.

A final tweaking of the Y output amplifier's many Rs and Cs, and it shows a really nice 3.5ns risetime.

Job done, and without touching my parts mule. Now to get rid of it somehow

[mnementh]

Congratulations, brother! Saved another one!!! 

mnem
"If It's Tuesday, This Must Be Belgium."

[beanflying]

hamfests are the devils playground!!!!

went to one down in Maryland this morning having taken a pledge not to touch.

came home with a freaking 7 segment led counter.  it is the only one I will admit to owning (with leds that is), and is ugly as sin.  (looks to me like a turtle had sex with a shoe box).  but except for one stuck slide switch it worked 100%.  in the picture it is counting a 456.789 Mhz signal from an hp 8640b.

tried to resist the hp power supply.....but it was so damn cute.  (and I actually thought to myself....WWND?)

the up side was that there was not much really to fix.  so after the fest crap was wiped down the bench was empty it was time to tackle the 3 each hp 5255a units that were all wonky and just taking up space in the "needs attention" stack.  did some board swapping, and between the 3 of them one is now working like a new one.  the pic shows a 5.9 Ghz signal from the crap rf explorer generator.  (the error is in the generator not the counter or heterodyne converter).

That Fluke is the Face and Body a Mother would put a bag over and leave on the steps of the orphanage 

There is also the Temperature version too, just what drugs was the industrial designer on 

[bd139]

Looks like the arse end of a Star Trek shuttle.

[nixiefreqq]

hamfests are the devils playground!!!!

went to one down in Maryland this morning having taken a pledge not to touch.

came home with a freaking 7 segment led counter.  it is the only one I will admit to owning (with leds that is), and is ugly as sin.  (looks to me like a turtle had sex with a shoe box).  but except for one stuck slide switch it worked 100%.  in the picture it is counting a 456.789 Mhz signal from an hp 8640b.

tried to resist the hp power supply.....but it was so damn cute.  (and I actually thought to myself....WWND?)

the up side was that there was not much really to fix.  so after the fest crap was wiped down the bench was empty it was time to tackle the 3 each hp 5255a units that were all wonky and just taking up space in the "needs attention" stack.  did some board swapping, and between the 3 of them one is now working like a new one.  the pic shows a 5.9 Ghz signal from the crap rf explorer generator.  (the error is in the generator not the counter or heterodyne converter).

That Fluke is the Face and Body a Mother would put a bag over and leave on the steps of the orphanage 

There is also the Temperature version too, just what drugs was the industrial designer on 

did they make them that way so that you could stack them and lock them together?

guess I need to go on a quest to find another one and do a test.   hope it does not wind up like something rude I once saw happening at the san diego zoo.

[beanflying]

There is a series of them including a Clip on Battery module. Rude little Frogs 





The Next Generation is 'better' 

[nixiefreqq]

geeeeeeze!   no wonder I stuck almost exclusively with hp.

that is a fugly pile o junk!

edit - hope saying that does not make inverted wanna' hunt me down and whoop my fat ass.   but geeeeeeeze!

[beanflying]

Fugly Fluke or Horny HP Freq, Dots and clip in Batteries. 

Not to mention Die-cast Aluminium vs Yellowed Plastic 

[bitseeker]

post #27248

"I just received the Fluke 8840A after some SAD.  Paid ~$50 total US."

I bought a Fluke 8842A at a fleamarket that looked in excellent condition but the seller said it had problems and was asking $20. They had removed the smoked display cover to use on another unit but other than that it looked great. They explained the problem was that the meter gave an error on A.C.. I talked them down to $16 and when I got it home found that it was within specs and that the A.C. option wasn't installed and that explained the error 30 it was displaying when you tried to use the A.C. function. I cut a piece of smoked plastic from an old HP counter to cover the display that looks halfway decent and now have a good back-up bench DMM.

Not bad. Not bad at all. Might a little alcohol rub off the remaining "Packard" on the smoked lens?

Robocop: "I'd buy that for a dollar!"

That's exactly the scene that went through my head as I read AD's post.

[nixiefreqq]

Fugly Fluke or Horny HP Freq, Dots and clip in Batteries. 

Not to mention Die-cast Aluminium vs Yellowed Plastic 

the 5300a system never made me want to shield my eyes.

was fixated by the dot leds and never noticed that the cases are maybe a little ugly.

[Tomorokoshi]

Fugly Fluke or Horny HP Freq, Dots and clip in Batteries. 

Not to mention Die-cast Aluminium vs Yellowed Plastic 

the 5300a system never made me want to shield my eyes.

was fixated by the dot leds and never noticed that the cases are maybe a little ugly.

Those case styles from both Fluke and HP come from their Disco phase.

[beanflying]

I have actually fuglied my 5300B/5305B a bit. The battery module came off the 5300A and has been reloaded with NiMh cells then strapped my GPSDO on top. (forgotten if I posted a pic here or not?)

8-10 Hours off grid GPSDO power or 3hours plus of Counter with GPSDO reference.

[bitseeker]

That Fluke is the Face and Body a Mother would put a bag over and leave on the steps of the orphanage 

There is also the Temperature version too, just what drugs was the industrial designer on 

I don't know, but he probably used a Hypospray.

Looks like the arse end of a Star Trek shuttle.

LOL! That it does, except for one thing...the shuttlecraft looks better. Nah, they're both ugly.

[nixiefreqq]

I have actually fuglied my 5300B/5305B a bit. The battery module came off the 5300A and has been reloaded with NiMh cells then strapped my GPSDO on top. (forgotten if I posted a pic here or not?)

8-10 Hours off grid GPSDO power or 3hours plus of Counter with GPSDO reference.

that's not too bad considering you did it for a specific purpose and its a one shot deal.

but if it had come from the factory that way it would make ya' say wtf.

[beanflying]

Its only 4 metal thread screws to split it if I ever decide to (drilled and tapped the internal factory case mounts). The only external mod was to the back of the Battery section to get the power out to the GPSDO. I don't 'currently' have any requirements to take the GPSDO on the road at all but it means it should never power down in the shack.

[jlw]

@Oculus: There's a matching ugly voltmeter to that counter. We should point him to one. That should keep NF occupied, so that he doesn't go looking for keys that did never belong there. Oh, and have someone put up a sign 'turtlepark' in his driveway.

I bought that ugly DMM at a flea market a few years ago.  The 2V and 200mV scales are dead; someday someone should fix them....   I passed up that very counter at the same flea market a week ago.  I have enough counters already, don't I?

[bitseeker]

I have enough counters already, don't I?

 

[beanflying]

I have enough counters already, don't I?

 

Is there such a thing? 

For a non Freq/Ham I am happy with my current five (3 of which were because of Nixie'itis) add to that a couple of fairly capable Arb generators with Freq inputs. That then led to a GPSDO and more recently an RF Generator in the fleet to help keep them in tune and now I am looking at ..... 

[Neomys Sapiens]

I always had a distinct zoological reminiscence with those brown Philips handheld multimeters (both digital and analogue, the better ones are not bad, btw). With their dark brown colours and drooping topsides - when I had two of them standing on top of a shelf, I was all the time reminded of sad little owls.

[mnementh]

   There is a series of them including a Clip on Battery module. Rude little Frogs 

   Hmmm... reminds me of these little gits. 

I have enough counters already, don't I?

mnem
 

[bitseeker]

I always had a distinct zoological reminiscence with those brown Philips handheld multimeters (both digital and analogue, the better ones are not bad, btw). With their dark brown colours and drooping topsides - when I had two of them standing on top of a shelf, I was all the time reminded of sad little owls.

Never seen those before. I like the analog one.

[Neomys Sapiens]

The analog one is a FET multimeter with high input impedance, auto-polarity and polarity indicator, quite like my Multizet A1000. (see 'show your multimeter).
The digital ones exist in LED and LCD, the top-end LCD has backlight and some additional functions, like RMS, min/max and a separate range and input for a RF probe. There was also a special version for the Philips X-Ray service people, which has some integration for mAh/s or something like that.
They are quite common as a series over here. German armed forces had a lot of them, so they are commonly seen with markings, but can be low usage.

[bitseeker]

The digital one has angles and facets like a stealth fighter aircraft.

[med6753]

(SNIP)

In other news, yesterday's GAS was yet another 465, this one with intact feet, two nibs on the cover, and it basically works. OK, some of CH1's ranges are peaky/touchy, and the trigger only works for >0.5 divisions, and some pots are scratchy, but with luck those should be fixable...

Famous last words... 

mnem
Best of luck, brother. See you on the other side.

For once it was better than I expected...

The LT power supplies were OK, and all had <500uV ripple.

The motor works fine.

Found scratchy pot couldn't b cracked open for some fader lube - but it didn't matter since rotating it a few times made it acceptable again.

I expected the twitchy/peaky CH1 deflection to be an attenuator problem. After cleaning the attenuator switches (an easyjob with IPA and a piece of paper), I noticed the problem appeared/disappeared when I attached/moved the input cable. So I heated all the flying solder joints between the input BNC connector and the attenuator board, and so far it is rock solid.

The trigger was, as I hoped, simply a case of tweaking the trimpots.

A final tweaking of the Y output amplifier's many Rs and Cs, and it shows a really nice 3.5ns risetime.

Job done, and without touching my parts mule. Now to get rid of it somehow

Are you going to do a beaded tant replace or just run until magic smoke? 

[Martin.M]

talking something analog.

that Krohn Hite 4100

is a Wien-Robinson Generator, made with interesting parts,
so the resistors in the generator filter network are selected to 0,1%, C to < 0,15%.
Some C have Krohn Hite Brand, selected to +0 -4% in parallel with a little C to get ±0,15% there also...
The square comes from a comparator following the sine oscillator.  We find 2 "IC" , black plastik blocks full of glue.
The instrument like high current amplifications, so it is warm and need 55W from AC

I have found it in the bay, "for repair". 27,-€ was enough to get the fun on the table.
"wrong frequencys, very distorted sine, square OK". Open Case and making some test.

picture1: distorted sine. true.

picture2:  For the regulating of the generator this instrument use a opto coupler.
In the (wrong) application, it came with papers from 4100A, is this part made from a LED and a LDR. So this cannot make problems,
but we have the 4100 here, not 4100A... here the LED is a little bulb, and this bulb was RIP = this is the problem.
Get a saw and make operation of that opto coupler, full with transparent glue. Cutted the bad bulb also, the rest of its glas is still in the glue, and nside is the spare bulb ,
there was some experiments to do to find the right voltage and current , then I got from Conrad some little bulbs and repair it.

picture3: 10kHz
picture4: the full 1MHz , there was nothing before.

cal.: the distortion have to be < 0,02% , up of 100kHz <0,1% up to 1MHz <1%.
DC Offset must be set very exactly bec. it have DC coupling to the output, otherwise a spectrum analyzer can be damaged by connect.
Case sheets can be washed in the dish washer machine.