Test Equipment Anonymous (TEA) group therapy thread

[AF6LJ]

My TEA is getting worse... TopLoser is killing me with those prices. Help please!

It's looking good.
Keep it up.

[Specmaster]

Argh yes, the Bedford TK and the Thames Trader, the best selling trucks of the period.

[Vgkid]

I'll definitely bring a few post-refurb shots here.  There will most likely be a longer thread started in the metrology section!

I look forward to this. I have an Azonix a1011 that I got cheap (thanks CataliniWOW) that works, just need to buy a pt100 rtd for it.

[bitseeker]

My TEA is getting worse... TopLoser is killing me with those prices. Help please!

Me too. 

The damn pusher got me twice already, and he is offering free shipping on my next fix. 

Think I have to become a member in here soon.

No one becomes a member here. That already happened out there and then we come here to post about it.

Welcome, eeviking.

[AF6LJ]

That's Cute ^^^^^

[djos]

My TEA is getting worse... TopLoser is killing me with those prices. Help please!

Me too. 

The damn pusher got me twice already, and he is offering free shipping on my next fix. 

Think I have to become a member in here soon.

No one becomes a member here. That already happened out there and then we come here to post about it.

Welcome, eeviking.

Coming to this thread is causing me to add things to my TE acquisition list, so I'm not sure it's helping ... or is it? 

[Cubdriver]

Coming to this thread is causing me to add things to my TE acquisition list, so I'm not sure it's helping ... or is it? 

Well, that's all relative to point of view.  Your credit card (and perhaps SWMBO) would say that it is not helping.  As a TEA 'sufferer', it's all good.   

 

-Pat

[djos]

Coming to this thread is causing me to add things to my TE acquisition list, so I'm not sure it's helping ... or is it? 

Well, that's all relative to point of view.  Your credit card (and perhaps SWMBO) would say that it is not helping.  As a TEA 'sufferer', it's all good.   

 

-Pat

It's motivating me to design and build more stuff for my retr0 buddies, which then funds acquisitions ... at least that's the theory. 

[mnementh]

What do you think about the Tek 2645, some people think it may be one of the best, if not the best scope they made?, 300Mhz and 4 channels?

I would say they are the best unitized scope Tek made... but there are a number of 7000 series modular scope configurations that beat it. It certainly was considered to be a reference standard for analog 'scope accuracy and performance for decades after its release, and the fact of being able to be sealed/calibrated for use as such was probably where that came from. That, and the fact that Tek calibration procedures for the 2465 specify another calibrated 2465 as required gear to do the calibration correctly.

I have one that has been on my bench since it was bought new by the company I worked for, one whose calibration history suggests it was in service at NASA around the time of the Shuttle missions, and another parts unit that I've used to keep the other two alive.

That and my 2230 were the heart of my bench for almost 20 years; now the 2230 has kakked a flyback AGAIN and I have a 1054Z serving right under the ol' 2465.

I do agree that they are a bit of a handful for amateur use; and decent 15-puff probes are not cheap anymore. The generic 100MHz probes everybody has will serve for most users; but if you REALLY need what the 2465 can do, they're going to distort the signal. What makes the 2465 so amazing is not what it's SUPPOSED to be able to do; it's what it CAN do that it shouldn't be able to.


Cheers,


mnem
moo?

[neo]

Well now i want a Tek 7904 with all of the modules listed.  It's going to be interesting to see how long it takes me to get one 

[neo]

While on the subject of oscilloscopes could some offer me some advice on how to better use mine? (Hitachi V-1065A) I got channel one connected to my function generator and then EXT Input directly to channel one and it locks onto any signal up to the 2.3 MHz limit of my function generator, though the triangle wave is very shaky.
I thought to myself this is progress i figured out how to make it lock onto a signal up to 2 MHz, so i tried to connect it to a 30MHz signal and the display completely lost it instead of displaying the signal it just displays a bar as opposed to the signal.
My exact settings regarding the trigger are TV-H and divide by 10, either i am missing something or it is not triggering properly at higher frequencies.

[bd139]

Sounds like wrong trigger setting. The bar is “rolling persistence”.  Try the following (working from a picture of the scope here):

1. Set it on auto trigger mode and make sure 20Mhz BW limit is off.
2. Connect your signal source to the probe on channel 1 or use a BNC or something. Make sure it’s a 10x probe if you’re using one as the 1x probe will not have enough bandwidth!
3. Set the source to channel 1
4. Change the channel 1 volts/div so the signal is at least 2 divs high.
5. Set the time base to fastest speed.
6. Slowly turn the trigger level control from full anti clockwise to clockwise and see if it locks.

That scope should trigger pretty well up to 120MHz or so.

[neo]

I've tried just that with no luck.

[bd139]

What connection and/or probes and generator are you using?

[neo]

The function generator with a 2MHz limit is Instek GFG-8020H, the probe is http://www.ebay.com/itm/1Pair-New-100MHZ-Oscilloscope-Clip-Probes-for-HP-Tektronix-Hitachi-1X-10X-TP6100-/381152195371?hash=item58be70f32b:g:g9UAAOSwpDdU2XhB
, and i had it connected to function generator directly with a bnc cable. The 30 MHz source is a ring oscillator which i am experimenting with for a circuit.

I also connected the scope to my Simpson 415A with a BNC and it worked fine up to 1.5MHz before rolling persistence kicked in on that one

[bd139]

In that case it sounds like the trigger is borked. Might just need cal steps running on it.

[neo]

I've always kinda thought of it as dodgy, maybe i was right to blame the instrument. Either ways forgive my ignorance but, cal steps?

[bd139]

Grab the service manual for it and run through the calibration steps (cal steps). This might require specialist equipment such as time-mark generators etc however but just have a scan through for any trigger calibration and check out steps.

[Specmaster]

Cal steps on a scope will almost certainly cause your TEA to get worse with the slow addition of yet more expensive and complicated test gear to set up the scope and so the cycle starts off again, it never stops, just keeps rolling along until lack of funds puts the brakes on 

[neo]

Lack of funding already has put a stop to the majority of my TEA.

In lighter news, SUCCESS! I connected channel 1 and 2 together and used channel 2 as the trigger and after alot of fine fiddling around with buttons i got it to lock onto and read the 30 MHz signal.

[Specmaster]

What scope are you using?

[neo]

Hitachi V-1065A. Interestingly enough i just spent a week trying to figure out how to make this scope work for frequencies this high just to see what the output could do, current wise, before collapsing.

Should a ring oscillators oscillation look like a sine wave?

[Specmaster]

Well that baby is good for 100Mhz and as such you should not require to provide any external sync signal to get the trigger to lock onto the incoming signal. It sounds as if it does need to be calibrated and you can do that job pretty well yourself. Keep an eye open on Ebay for a Heathkit IG4505 and you can do it reasonably well with that without all other expensive kit provided you don't require it to be calibrated to Lab standards.

shows how to use this unit.

[neo]

I think mine may be slightly dodgy, using it has always been possible given the right amount of time but trying to get it to lock onto 30MHz has been like pulling teeth.

[Specmaster]

Like bd139 said, if you do the cal steps you might find that it works far better. I have 4 working scopes right now (had 6 at one time but sold 2 and I'm working another 2 on the bench as well) and in almost each case when I acquired them they were not performing correctly. Opening them up and cleaning the switches and controls made a lot improvements in their performance. Have you watched the video, he does make the point that you could surround yourself with a load of other high cost equipment to do the same job as the Heathkit unit.