Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Slightly off topic but reading about batteries exploding etc, not that much off then.

Been watching a few videos of fires both here in the UK and in the USA as well as Europe and it strikes me that the fire depts in USA could learn a thing or two from the rest of us. It seems to me that the USA trucks don't carry any water on board and when they arrive at the scene, they wast valuable time looking around for a fire hydrant and then running hoses to it from the truck and then hoses out to the fire. By which time the buildings are often lost causes and others suffer as a result.

Does anyone actually know why they don't carry some water on their trucks at all?

I'm not sure where you got that impression. Your videos might be mostly CITY fire departments where they have fire hydrants. No such animal where I live and ALL the local fire depts have large tanker trucks to provide water.

You are correct, there were city depts, still makes no sense me at all as watching them getting set up, the fire goes from bad to worse, sometimes being a total loss before they bring water to the fire. I did see one USA dept in the countryside that took 2 big water tankers to a fire that consumed 3 houses before they could control it, this despite the fact there was a large river at the rear of the house were they could have dropped hoses into for a supply 

Contrasted that to a house fire in Oxford UK that took out the roofs of the 2 houses that were semi detached and because we always carry water, they had hose's supplying water to the fire within 28 seconds of arriving at the scene and the 2 houses were as a result saved with minor damage, verses total losses over the pond of 3 houses (started with the one) and they are all completely detached as well  Not that its a laughing matter really but what a difference it makes with a well trained and disciplined team that carry enough water to a scene to enable water to be used early in the process while others hunt down a hydrant to provide continuous supply

I still don't know where you get these impressions. It's standard practice to set up a pumper/tanker near an above ground water source and draw from it if one is close by...and there usually is. But if not they call in additional fire depts with their tanker trucks to provide water.
 

[med6753]

Bloody hell that thing is enormous.

... but not very long by US standards.

If you have to wait for one at a level crossing, it becomes very tedious as it continues to trundle past for what seems like an eternity.

Well yes, but the big boy will not be put back into regular service. Standard freight consist is usually 2 to 4 4000HP diesel-electric locos with at least 100 to 125 rolling stock. Some as much as 200 rolling stock.

[bd139]

Don't think you could fit one of those trains in our country 

[med6753]

More work on the 7904. Specifically the plug-ins that came with it. This is the 7A26 2 channel 200MHz plug-in. Some intermittent contacts in both attenuator decks. Cleaned up fine with 100% IPA and heat gun to dry. Checked compensation and perfect on both channels. Here's 10MHz square wave. She's perfect. 

Next up is the 7A24 2 channel 400MHz/50 ohm plug-in. I think this one is gonna be a problem child. We'll see. 

[med6753]

Don't think you could fit one of those trains in our country 

  Freight trains of that size are common even here on the East Coast. 

[GregDunn]

I know many of you were concerned about inverted18650. This ebay listing came up in my saved searches this morning:

https://www.ebay.com/itm/401763768254

Description says: "Formerly iDG/ Inverted18650. Selling everything in the shop due to medical condition. Everything must go, including domain names etc. Check my other items and buy with confidence. Thank you for looking and Cheers."

So it sounds like he's still with us, although the concerns about his health unfortunately were justified.

Perhaps someone could use a nice-looking 34401 for a decent price, and help him out with medical expenses while you're at it?

Located in Clarksville, TN. Sounds like him.

This does sound concerning.  We had been discussing a couple of TE items (which I was prepared to offer a fair price for, as well as picking them up myself) but that was about when he went silent.  I'm still hoping we can make that connection, because it would help both of us out.

[med6753]

Why am I smelling burnt chicken? Why IS my chicken burnt? You jackass, you had the oven set to "broil" rather than "bake".

Enjoy your burnt chicken you dope.   

[med6753]

I know many of you were concerned about inverted18650. This ebay listing came up in my saved searches this morning:

https://www.ebay.com/itm/401763768254

Description says: "Formerly iDG/ Inverted18650. Selling everything in the shop due to medical condition. Everything must go, including domain names etc. Check my other items and buy with confidence. Thank you for looking and Cheers."

So it sounds like he's still with us, although the concerns about his health unfortunately were justified.

Perhaps someone could use a nice-looking 34401 for a decent price, and help him out with medical expenses while you're at it?

Located in Clarksville, TN. Sounds like him.

This does sound concerning.  We had been discussing a couple of TE items (which I was prepared to offer a fair price for, as well as picking them up myself) but that was about when he went silent.  I'm still hoping we can make that connection, because it would help both of us out.

Hope so because I lost money on this whole deal. He offered to send me a Tek 7704 no charge. I offered to pay shipping and I sent him $85 USD. Well that didn't happen and we decided instead to meet in PA and he would use the $85 for gas. That didn't happen either and I guess the $85 is gone with the wind. I'm a little annoyed about it but what are you gonna do?   

[mnementh]

Slightly off topic but reading about batteries exploding etc, not that much off then.

Been watching a few videos of fires both here in the UK and in the USA as well as Europe and it strikes me that the fire depts in USA could learn a thing or two from the rest of us. It seems to me that the USA trucks don't carry any water on board and when they arrive at the scene, they wast valuable time looking around for a fire hydrant and then running hoses to it from the truck and then hoses out to the fire. By which time the buildings are often lost causes and others suffer as a result.

Does anyone actually know why they don't carry some water on their trucks at all?

It depends on the unit. There are "Pumpers" and there are "Pumper-Tankers". E-32, our "First Responder" rig, was a pumper-tanker. It was a full-spec pumper in it own right, carrying 2500 gal water as well as foaming agent.

It seems to depend on the department as to what is considered "common application". Rural departments tend to have to deal with brushfires and MVAs without close proximity to hydrants; tankers and pumper-tankers are a necessity. Brushfires especially, quick knockdown is essential. The first 5 minutes on-scene can make the difference between a 30-minute routine call and an all-day marathon.

Urban departments have the luxury of being able to depend on hydrants; though it still seems stupid to me to NOT have some tank capacity on a first responder rig, where being able to hit the fireline in the first 90 seconds on scene can cut damage in half. And yes, I've seen more than a few urban firegrounds where there were no tankers or pumper-tankers; now whether that was a matter of local procedure or simply availability, I don't know.

If you're looking at news footage, remember that they're rarely on scene until the firefight is half-over; when they get there, they're going to shoot where the activity seems most interesting, which would tend to be around setting up a pumper. And of course, news vans tend to get "cordoned off" with extreme prejudice, so the pumper close to a hydrant may very well be as close as they can get to the action. 

mnem

[0culus]

Don't think you could fit one of those trains in our country 

  Freight trains of that size are common even here on the East Coast.

BNSF has been running 14k foot stackers out west for a while. Typically have distributed power mid-train and at the rear too.

[mnementh]

Jeebus... that's over 2 1/2 miles. Get stuck on the wrong side of one of those at a crossing, you may as well turn around and go have lunch. 

Got some other freebies while I was picking them up...

Those power conditioners are worth more than the whole rest of the lot put together. 

...However, it's not HP (a direction in which I seem to have found myself heading) and it's definitely not in the budget.  Looks cool, though.

Compaq most definitely IS HP. Has been for decades.

Bloody hell that thing is enormous.

I think our best effort over here is the class 91. 6480hp but electric.

^{A million pounds plus of iron & smoke. And blood, sweat & tears I'm sure. The whistle is hardly the most impressive part of THAT presence.} 

Why am I smelling burnt chicken? Why IS my chicken burnt? You jackass, you had the oven set to "broil" rather than "bake".

Enjoy your burnt chicken you dope.   

Looks like this penis fingers phenomenon is expanding its sphere of influence. Maybe I need to rethink my move, if only for the safety of my loved ones. 

mnem
*currently trying to bodge the starter wiring on a palletized Ecotec 2.2 engine so I can take compression readings*

[med6753]

OK, here's the 50 ohm/400MHz 7A24 plug-in. Much different attenuator arrangement that I've not seen before. And yes, as I suspected it has problems. It has "fuses" in there and it looks like some are open.

Channel 1: 50mV and .5V dead. Channel 2: .1V up to 1V all dead. I have to RTFM in order to troubleshoot any further. It does have spare fuses and I have to figure out how to change them. And if I need more I wonder if they are available?

Anyway, what I was able to check looks real good. Checked 1KHz compensation on functioning ranges and it's good. And here is channel 1 at .2V displaying at 20MHz square wave.   Looks good! 



 

[mnementh]

I'm going to keep my mouth shut so as not to invite Murphy. 

mnem

Why the long face?

[0culus]

OK, here's the 50 ohm/400MHz 7A24 plug-in. Much different attenuator arrangement that I've not seen before. And yes, as I suspected it has problems. It has "fuses" in there and it looks like some are open.

Channel 1: 50mV and .5V dead. Channel 2: .1V up to 1V all dead. I have to RTFM in order to troubleshoot any further. It does have spare fuses and I have to figure out how to change them. And if I need more I wonder if they are available?

Anyway, what I was able to check looks real good. Checked 1KHz compensation on functioning ranges and it's good. And here is channel 1 at .2V displaying at 20MHz square wave.   Looks good! 

The 7A19 amplifier I have has that style of fuse as well on the attenuator deck. Also has spares inside. No idea how to change them. 

[0culus]

Jeebus... that's over 2 1/2 miles. Get stuck on the wrong side of one of those at a crossing, you may as well turn around and go have lunch. 

*snip*

14,500 feet. 248 cars.  And a lot of horsepower.  Also RIP to any poor conductor that has to walk that train looking for a stuck brake or something.  [edit] 5 minutes into the video, the mid train power finally makes an appearance.

[med6753]

OK, here's the 50 ohm/400MHz 7A24 plug-in. Much different attenuator arrangement that I've not seen before. And yes, as I suspected it has problems. It has "fuses" in there and it looks like some are open.

Channel 1: 50mV and .5V dead. Channel 2: .1V up to 1V all dead. I have to RTFM in order to troubleshoot any further. It does have spare fuses and I have to figure out how to change them. And if I need more I wonder if they are available?

Anyway, what I was able to check looks real good. Checked 1KHz compensation on functioning ranges and it's good. And here is channel 1 at .2V displaying at 20MHz square wave.   Looks good! 

The 7A19 amplifier I have has that style of fuse as well on the attenuator deck. Also has spares inside. No idea how to change them. 

Well as soon as I find out I'll let you know. Obviously the gorilla has been on the loose again and burned some of them out.  Some techs just don't get that 50 ohm inputs are delicate and can't stand overloads. 

[0culus]

Yeah, you really have to stop and think before you apply a signal. Fortunately the 7A19 is slightly more robust than some 50 ohm amplifiers. 5V RMS on .1 volt/div and 10V RMS above that. The delicate part is 50 mV/div and below. 10 mV can only handle .5 V RMS. 

[GregDunn]

This does sound concerning.  We had been discussing a couple of TE items (which I was prepared to offer a fair price for, as well as picking them up myself) but that was about when he went silent.  I'm still hoping we can make that connection, because it would help both of us out.

Hope so because I lost money on this whole deal. He offered to send me a Tek 7704 no charge. I offered to pay shipping and I sent him $85 USD. Well that didn't happen and we decided instead to meet in PA and he would use the $85 for gas. That didn't happen either and I guess the $85 is gone with the wind. I'm a little annoyed about it but what are you gonna do? 

   Yeah, that sucks - we were on the verge of working out a visit so I could help him test and sort a few bits of TE and collect a HP3456A he was holding for me; that was about the time his health started causing issues.  But enough about that - speculation is pointless; with luck, we'll hear from him before much longer.

[bd139]

Yeah, you really have to stop and think before you apply a signal. Fortunately the 7A19 is slightly more robust than some 50 ohm amplifiers. 5V RMS on .1 volt/div and 10V RMS above that. The delicate part is 50 mV/div and below. 10 mV can only handle .5 V RMS. 

Looking at the schematic I’m surprised that front end is as fragile as it is. I assume the attenuator is the most tetchy bit.

[0culus]

This does sound concerning.  We had been discussing a couple of TE items (which I was prepared to offer a fair price for, as well as picking them up myself) but that was about when he went silent.  I'm still hoping we can make that connection, because it would help both of us out.

Hope so because I lost money on this whole deal. He offered to send me a Tek 7704 no charge. I offered to pay shipping and I sent him $85 USD. Well that didn't happen and we decided instead to meet in PA and he would use the $85 for gas. That didn't happen either and I guess the $85 is gone with the wind. I'm a little annoyed about it but what are you gonna do? 

   Yeah, that sucks - we were on the verge of working out a visit so I could help him test and sort a few bits of TE and collect a HP3456A he was holding for me; that was about the time his health started causing issues.  But enough about that - speculation is pointless; with luck, we'll hear from him before much longer.

I'd like to help him out by purchasing something like that HP multimeter, but this makes me nervous about doing so.

Yeah, you really have to stop and think before you apply a signal. Fortunately the 7A19 is slightly more robust than some 50 ohm amplifiers. 5V RMS on .1 volt/div and 10V RMS above that. The delicate part is 50 mV/div and below. 10 mV can only handle .5 V RMS. 

Looking at the schematic I’m surprised that front end is as fragile as it is. I assume the attenuator is the most tetchy bit.

Probably. I think everything is well protected by the fuses. The input has a warning "Excess voltage will blow int fuse".

[med6753]

All work and no play makes for a dull boy. Now that the 7904 mainframe is finished time for a little playing around. The set up: two 7A26 vertical plug-ins and two 7B80 timebase plug-ins. 10KHz square on channel 1. 10KHz sine on channel 2. Vertical ALT mode. Timebase ALT mode. One 7B80 set to 50us. One 7B80 set to 100us. Way cool! 



Been a very successful past few weeks with repairs......

Two 465B's fixed
2430 fixed (several times  )
7904 fixed.

Murphy be damned. 

[mnementh]

"FOUR...! Fourrrr voorrkeeng Ah-nahh-log scopes! Ahhh-ahhh-ahhhh!"

mnem
What....?

[beanflying]

I may not need rack ears - there were several shelves included.  However, it's not HP (a direction in which I seem to have found myself heading) and it's definitely not in the budget.  Looks cool, though.

The really frustrating part, though, was that at the pickup, the guy had 1 piece of rack stripping, 16 units high.  If he had a second piece, I could whip up a timber frame and get myself the bench side rack I have mentioned before.  We looked high and low, but no luck.  Finding a second such piece would have made the whole exercise of getting those 2 cabinets down a flight of stairs worth the pain.

Ahhh .... you're widening the rabbit hole again!

Additional Interior design ideas because I like to 'assist'

[Neomys Sapiens]

Bloody hell that thing is enormous.

I think our best effort over here is the class 91. 6480hp but electric.

Class 92 5.04MW/6760hp when under 25kV AC
and controlled by MICAS-S2, my ass. I did a prototype GPS connection to that system together with a study on the applications of satellite navigation to railways back in '95.
I always liked those multisystem engines, like our 184 or 189ers.
Class 93 will be rather a step back power-wise, and I can't agree that everything is better with batteries.
But you should be allowed to count the class 9, which have a lot of UK content (and none french ), with their respectable 7MW.

[Neomys Sapiens]

OK, here's the 50 ohm/400MHz 7A24 plug-in. Much different attenuator arrangement that I've not seen before. And yes, as I suspected it has problems. It has "fuses" in there and it looks like some are open.

Channel 1: 50mV and .5V dead. Channel 2: .1V up to 1V all dead. I have to RTFM in order to troubleshoot any further. It does have spare fuses and I have to figure out how to change them. And if I need more I wonder if they are available?

Anyway, what I was able to check looks real good. Checked 1KHz compensation on functioning ranges and it's good. And here is channel 1 at .2V displaying at 20MHz square wave.   Looks good! 

The 7A19 amplifier I have has that style of fuse as well on the attenuator deck. Also has spares inside. No idea how to change them. 

I think that you have to slide the metal tab towards the closed side, so that the larger hole is in position. Then lift the closed side off the post and slide futher in the same direction until the side with the open slot comes off the other post.