Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Yes, which means they have value as sacrificial elements if nothing else. If they are indeed these mythic shitsistors you speak of, you can get your fix of magic smoke without having to waste DECENT resistors! 

Alternately, useful as a potential source of oddball values between EIA standard values for quick breadboarding, etc. Point being, there is no such thing as a useless resistor unless it's one that's already been burned up.

mnem
bd like to use Shi-tzus as fusible resistors. 

[bd139]

I can afford to waste decent resistors on magic smoke opportunities  (4000x TE LR1F100R)



The problem is the tempco on the cheap ones which can shoot past 500ppm/oC easily 

With a full set of E6 you can make any value you need easily. I have a book of Royal Ohm E24 and a tub of E6's (edit: plus a growing selection of RN55D's which is getting expensive  )

[xrunner]

I know!

Straighten it all out on the floor.
Solder all the leads on both sides all the way down from one end to the other.
Apply to Guinness world records for the most amount of resistors ever soldered in parallel. 

I can afford to waste decent resistors on magic smoke opportunities  (4000x TE LR1F100R)



The problem is the tempco on the cheap ones which can shoot past 500ppm/oC easily 

With a full set of E6 you can make any value you need easily. I have a book of Royal Ohm E24 and a tub of E6's

[Mr. Scram]

There's cheap and there's too cheap. If the Ferengi feels it's a worthwhile investment I'm not going to argue.

[bd139]

I know!

Straighten it all out on the floor.
Solder all the leads on both sides all the way down from one end to the other.
Apply to Guinness world records for the most amount of resistors ever soldered in parallel. 

Actually that's not far off what I tend to do with those. They get used as 50 ohm loads. You can mesh them into blocks easily or just use two for a good 50 ohm match. Good to 200+ MHz

There's cheap and there's too cheap. If the Ferengi feels it's a worthwhile investment I'm not going to argue.

Yeah that's exactly it. Time isn't cheap.

The box of TE resistors above was a bit of a win. Specmaster and myself participated in taking advantage of a pricing error on RS. Think they were about £4 for 1000 a box instead of £25. And then boxes of 4000 turned up! 

[mnementh]

mnem

[Specmaster]

Well, this is embarrassing and a mystery. The roll off on this 465B IS due to the attenuators being completely fubar and needing adjustment. I don't get it, I would never complete a project and leave it in this condition. This was the same 465B where I had to completely replace the channel 2 switch deck. I know I went thru the adjustment procedure and I checked my notes. But no matter. Both channels need to be set properly. Going through that now.   

Also, this replacement pre-amp board is working fine however the DC balance on both channels and the Invert balance on channel 2 were literally off the screen. I smell monkey twist pot when this board was in the parts mule in a lame attempt at some sort of repair. But that's fixed now too. 

Maybe its just telling you that it wants to be left in peace after its long working life and just be able to, like you, enjoy its retirement 

[mnementh]

There's cheap and there's too cheap. If the Ferengi feels it's a worthwhile investment I'm not going to argue.

I generally agree with this. however, I would NOT buy anything from that MPJA sale I wasn't already interested in anyways, so the "free" resistor pack would be truly free, and I'd get to see what shows up. When they get there I'd test 'em quick, and if I found any that didn't please me, out they'd go. Not like it's any scale off my arse one way or t'other. I can't count the number of name-brand resistors I've bought over the decades off eBay for the $4-6 they value these kits at. 

Bottom line is we're making assumptions based on a grainy pic in a sale flyer and the Ferengi's hard-wired "sour grapes" attitude.  Meanwhile, the whole world runs on those shitty Chinese resistors, for the most part. 

Cheers,

mnem
It's a fucking resistor, man.

[bd139]

It's a fucking resistor, man.

Bob Pease is going around like a gas turbine in his grave at the moment 

[Specmaster]

I know!

Straighten it all out on the floor.
Solder all the leads on both sides all the way down from one end to the other.
Apply to Guinness world records for the most amount of resistors ever soldered in parallel. 

Actually that's not far off what I tend to do with those. They get used as 50 ohm loads. You can mesh them into blocks easily or just use two for a good 50 ohm match. Good to 200+ MHz

There's cheap and there's too cheap. If the Ferengi feels it's a worthwhile investment I'm not going to argue.

Yeah that's exactly it. Time isn't cheap.

The box of TE resistors above was a bit of a win. Specmaster and myself participated in taking advantage of a pricing error on RS. Think they were about £4 for 1000 a box instead of £25. And then boxes of 4000 turned up! 

Yep and I've flipped loads of mine on evilbay 

[Specmaster]

Attention all you UK based Heathkit fanboys, just stumbled across this I0-103 in good condition on GumTree, a bit on the pricey side but you may be able to strike a deal.

https://www.gumtree.com/p/for-sale/heathkit-oscilloscope-model-io-103/1352071010?utm_source=savedsearches&utm_medium=email&utm_campaign=GT.TRIGGER.SA&utm_content=none&utm_source=savedsearches&utm_medium=email&utm_campaign=GT.TRIGGER.SA&utm_content=none

[bd139]

Bloody hell that thing's worth about 20 quid. I think it's on ebay as well for same stupid amount of money.

I've got my eye on something else at the moment that was just listed 

[mnementh]

It's a fucking resistor, man.

Bob Pease is going around like a gas turbine in his grave at the moment 

I know.

mnem

This message approved by
The Department of Irradiation.

[mnementh]

Bloody hell that thing's worth about 20 quid. I think it's on ebay as well for same stupid amount of money. I've got my eye on something else at the moment that was just listed 

It is in crazy excellent condition... and it IS in the "correct" grey-brown crinkle finish... but that price is still just starkers. 

[Devil's Advocate Mode] Or is it...? If it really is as pristine as it looks... is $250 REALLY too much for a museum-quality example of ANYTHING? Adjusted for inflation, still less than half what it cost new, I'll wager... [/Devil's Advocate Mode]

mnem
 

[bd139]

They actually had those scopes and a couple of older Heathkit valve ones when I was at school. This was an excuse by the physics department head to get someone else to pay for him to build the kits  . AFAIK he actually took them home and built them and the school got value for money out of this. Then he took them home when they were obsolete 

They're not bad and they did a couple of dual channel much faster ones if I remember.

But still the graticule on the shield is just horrible. I hate scopes like that.

[med6753]

Bloody hell that thing's worth about 20 quid. I think it's on ebay as well for same stupid amount of money.

I've got my eye on something else at the moment that was just listed 

Agreed....$50 USD at the most. They are freaking nuts asking that price.

[med6753]

Somebody shoot me and put me out of my misery.  Did I mention that this 465B is my problem child? Yes, too many times. And it continues to be that bat shit crazy redhead and family shame.  The compensation adjustments of the attenuators were going OK until I decided to do some high frequency checks. At 1MHz the square wave resembled a sick sine. WTF? Long story short.....this pre-amp board apparently has had all it's trimmers and pots monkeyed with. I should have taken the clue when I found the DC balances on both channels way off. So I had no choice but to pull the board and install the original board....which I know is good, AND...has had all it's tants changed. Now things are looking ALOT better but I have to go through all the compensation adjustments again. Fuck me.   

[med6753]

Bloody hell that thing's worth about 20 quid. I think it's on ebay as well for same stupid amount of money. I've got my eye on something else at the moment that was just listed 

It is in crazy excellent condition... and it IS in the "correct" grey-brown crinkle finish... but that price is still just starkers. 

[Devil's Advocate Mode] Or is it...? If it really is as pristine as it looks... is $250 REALLY too much for a museum-quality example of ANYTHING? Adjusted for inflation, still less than half what it cost new, I'll wager... [/Devil's Advocate Mode]

mnem
 

If I had it I would spray it blue just to piss you off. 

[bd139]

Hahahaha 

[mnementh]

Bloody hell that thing's worth about 20 quid. I think it's on ebay as well for same stupid amount of money. I've got my eye on something else at the moment that was just listed 

It is in crazy excellent condition... and it IS in the "correct" grey-brown crinkle finish... but that price is still just starkers. 

[Devil's Advocate Mode] Or is it...? If it really is as pristine as it looks... is $250 REALLY too much for a museum-quality example of ANYTHING? Adjusted for inflation, still less than half what it cost new, I'll wager... [/Devil's Advocate Mode]

mnem
 

If I had it I would spray it blue just to piss you off.

And if I had it... I'd ship it out to you. Even knowing that...

mnem
Media Mail. Wrapped on all side in layers of old Japanese Manga books full of tentacle pr0n.

[xrunner]

Long story short.....this pre-amp board apparently has had all it's trimmers and pots monkeyed with. I should have taken the clue when I found the DC balances on both channels way off.

They were just trying to get it to display a 20 GHz signal. Can you blame them? 

[tautech]

Somebody shoot me and put me out of my misery.  Did I mention that this 465B is my problem child? Yes, too many times. And it continues to be that bat shit crazy redhead and family shame.  The compensation adjustments of the attenuators were going OK until I decided to do some high frequency checks. At 1MHz the square wave resembled a sick sine. WTF? Long story short.....this pre-amp board apparently has had all it's trimmers and pots monkeyed with. I should have taken the clue when I found the DC balances on both channels way off. So I had no choice but to pull the board and install the original board....which I know is good, AND...has had all it's tants changed. Now things are looking ALOT better but I have to go through all the compensation adjustments again. Fuck me. 

Look on the bright side, if only adjustments bring it back into line and nothing needs replacing you've beaten the gorilla that was there before you ! 

[med6753]

It ain't perfect but it's done. The total compensation cal procedure is extremely complex and I don't have the proper equipment so I make due. The results are acceptable.

10MHz square wave from the Heath IG-4244 Scope Calibrator. Not bad. Could be a little better but I can live with it.



And 5kHz test signals. Looks real good. This one is FINALLY done....until it breaks again. 

[med6753]

Somebody shoot me and put me out of my misery.  Did I mention that this 465B is my problem child? Yes, too many times. And it continues to be that bat shit crazy redhead and family shame.  The compensation adjustments of the attenuators were going OK until I decided to do some high frequency checks. At 1MHz the square wave resembled a sick sine. WTF? Long story short.....this pre-amp board apparently has had all it's trimmers and pots monkeyed with. I should have taken the clue when I found the DC balances on both channels way off. So I had no choice but to pull the board and install the original board....which I know is good, AND...has had all it's tants changed. Now things are looking ALOT better but I have to go through all the compensation adjustments again. Fuck me. 

Look on the bright side, if only adjustments bring it back into line and nothing needs replacing you've beaten the gorilla that was there before you ! 

That board is going into the spare parts box to be raided for parts as needed.

[bd139]

Just won some more HP goodness. I really don't need it but it was in pretty good condition. 5316B 



Not sure what timebase it has in it but if it's a poo one I have an excuse to build a replacement OCXO

Edit: just realised I'm going to need a common frequency standard now and distribution for it. Hmm can of worms now opened