Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Is it proper TEA if you make it yourself?

Depends what you mean by "proper".   For me, I would ask: Is it Equipment used for Testing (in any sense)?   Your answer to that would be my answer to your question.

It's theft, isn't it? All Proper TEA is theft 

Huh....?   

I'd argue that bespoke TE is the epitome of TEA...

mnem
*tzzzzzt*

[capt bullshot]

Just read the newsletter from German computer magazine c't:

They've asked their readers what this unit is and what it would be used for in their lab:



BTW: I've already submitted my answer to them and there's no prize to win, so no point in hiding your answers here ...

[nixiefreqq]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Got this in the same Craigslist transaction as the Heath Zenith HV DC power supply. Some middle-age guy was selling TE before moving. It came with the original Operation Manual and the Service Manual.

I had to remove cal stickers to open the case, which is a good sign. I saw a few date codes of '91 and then quickly buttoned it up again. There is a calibration sticker on it from '06.

Made in Japan. Solid as a brick dunny. Looks expensive. I notice that the mains input autoranges across Japanese and US voltages and frequencies.

It seems to work OK up to 20Mhz (which is as high as my signal generator will go).

Why? I've always wanted an SA. More recently, I've started down the slippery slope of radio. I've started with GMRS (license is USD35, no test) which is 462-467Mhz. I would dearly love an SA that goes down to 0Hz (for audio work), but those are far too dear for me to justify at this point.

I'm now in the market for an N connector dust cap, cables, adapters, attenuators, and a signal generator that goes up to 500MHz or so.

EDIT:

Test setup is Rigol DG1022 -> 50 Ohm BNC cable -> BNC to N connector adapter -> SA. I know enough to know that I don't know what I'm doing when it comes to RF. I was very careful to figure out a nice low output level (1V RMS) that would not damage the SA.

EDIT EDIT:

Also came with a box of cables and adapters that I'm not able to judge yet, but it looks more Aliexpress than [hp].

EDIT^3:

https://www.opweb.de/english/company/Anritsu/downloads/Anritsu--MS610B--user--ID4283.pdf - User manual 20MB scan

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

[McBryce]

Oooo.... Parcel of non-announced hollow-state TE just arrived

McBryce.

[mnementh]

It's theft, isn't it? All Proper TEA is theft 

Huh....?   

mnem
*tzzzzzt*

Oh... "La propriété, c'est le vol!"  *groannnnn*

mnem
*lobs 1½ soggy old boots at nfmax*  "Y'all git offa mah property!!!"

[Vince]

Oooo.... Parcel of non-announced hollow-state TE just arrived

McBryce.

Wow, a boat anchor !! 

Didn't know you were into that sort of stuff, your picture shows only modern solid state stuff, got mistaken my bad.

But your lab looks so short on space, where are you going to put this huge piece of vintage TE ?! 

Maybe hang it from the ceiling ?! 

But that's your problem not mine, all I care about is to see what's in the box !!! 

A Tek 547 ?! 

Open up the box quick,  will you !!! 

[Vince]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

About that, and not having an SA myself nor knowing much about them.... I always wondered... since it's so easy to blow the front end, and since these instruments cost a tremendous amount of money... it always begged the obvious question : WHY the hell don't SA manufacturers protect their damn front-end in the first place ?!   

Of course I am sure there is an obvious technical reason why that's not possible, and any SA owner knows about it.... but I don't. So please educate me if you have 30 seconds between two refills of your cup of tea/coke/coffee....

From what I see in voltmeters or even the RF front end of pre-scalers in  multi GHz counters, the input is often protected by a couple of diodes that limit the voltage to a defined level. Then a resistor is put in series with the input, so as to limit the current going through the diodes, so as not to blow them, should they be solicited ...
Why can't that be done as well to protect against over voltage / too large signals on a SA ? or a variation o fit, or something else entirely that might be more suitable, I don't know.... SOMETHING !!! 


Thanks.

Yours Truly.

[Kosmic]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Got this in the same Craigslist transaction as the Heath Zenith HV DC power supply. Some middle-age guy was selling TE before moving. It came with the original Operation Manual and the Service Manual.

I had to remove cal stickers to open the case, which is a good sign. I saw a few date codes of '91 and then quickly buttoned it up again. There is a calibration sticker on it from '06.

Made in Japan. Solid as a brick dunny. Looks expensive. I notice that the mains input autoranges across Japanese and US voltages and frequencies.

It seems to work OK up to 20Mhz (which is as high as my signal generator will go).

Why? I've always wanted an SA. More recently, I've started down the slippery slope of radio. I've started with GMRS (license is USD35, no test) which is 462-467Mhz. I would dearly love an SA that goes down to 0Hz (for audio work), but those are far too dear for me to justify at this point.

I'm now in the market for an N connector dust cap, cables, adapters, attenuators, and a signal generator that goes up to 500MHz or so.

EDIT:

Test setup is Rigol DG1022 -> 50 Ohm BNC cable -> BNC to N connector adapter -> SA. I know enough to know that I don't know what I'm doing when it comes to RF. I was very careful to figure out a nice low output level (1V RMS) that would not damage the SA.

EDIT EDIT:

Also came with a box of cables and adapters that I'm not able to judge yet, but it looks more Aliexpress than [hp].

EDIT^3:

https://www.opweb.de/english/company/Anritsu/downloads/Anritsu--MS610B--user--ID4283.pdf - User manual 20MB scan

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

Just to scare you a bit more,

Blown attenuator pads from a Tektronix 2794 SA





Finally, the limiter (just after the attenuator) also died. But the damages are less apparent.



P.S: I got the instrument broken and was not responsible for all this. A gorilla probably fed multiple Watt into the poor thing.

[tggzzz]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

About that, and not having an SA myself nor knowing much about them.... I always wondered... since it's so easy to blow the front end, and since these instruments cost a tremendous amount of money... it always begged the obvious question : WHY the hell don't SA manufacturers protect their damn front-end in the first place ?!   

Of course I am sure there is an obvious technical reason why that's not possible, and any SA owner knows about it.... but I don't. So please educate me if you have 30 seconds between two refills of your cup of tea/coke/coffee....

From what I see in voltmeters or even the RF front end of pre-scalers in  multi GHz counters, the input is often protected by a couple of diodes that limit the voltage to a defined level. Then a resistor is put in series with the input, so as to limit the current going through the diodes, so as not to blow them, should they be solicited ...
Why can't that be done as well to protect against over voltage / too large signals on a SA ? or a variation o fit, or something else entirely that might be more suitable, I don't know.... SOMETHING !!! 


Thanks.

Yours Truly.

In one word, intermodulation.

Spectrum analysers are required to have a wide dynamic range which implies extreme linearity. (Any non-linearity introduces distortion and intermodulation)

Protection components are inherently nonlinear, even when not needing to do any protection.

[bd139]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Got this in the same Craigslist transaction as the Heath Zenith HV DC power supply. Some middle-age guy was selling TE before moving. It came with the original Operation Manual and the Service Manual.

I had to remove cal stickers to open the case, which is a good sign. I saw a few date codes of '91 and then quickly buttoned it up again. There is a calibration sticker on it from '06.

Made in Japan. Solid as a brick dunny. Looks expensive. I notice that the mains input autoranges across Japanese and US voltages and frequencies.

It seems to work OK up to 20Mhz (which is as high as my signal generator will go).

Why? I've always wanted an SA. More recently, I've started down the slippery slope of radio. I've started with GMRS (license is USD35, no test) which is 462-467Mhz. I would dearly love an SA that goes down to 0Hz (for audio work), but those are far too dear for me to justify at this point.

I'm now in the market for an N connector dust cap, cables, adapters, attenuators, and a signal generator that goes up to 500MHz or so.

EDIT:

Test setup is Rigol DG1022 -> 50 Ohm BNC cable -> BNC to N connector adapter -> SA. I know enough to know that I don't know what I'm doing when it comes to RF. I was very careful to figure out a nice low output level (1V RMS) that would not damage the SA.

EDIT EDIT:

Also came with a box of cables and adapters that I'm not able to judge yet, but it looks more Aliexpress than [hp].

EDIT^3:

https://www.opweb.de/english/company/Anritsu/downloads/Anritsu--MS610B--user--ID4283.pdf - User manual 20MB scan

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

Just to scare you a bit more,

Blown attenuator pads from a Tektronix 2794 SA





Finally, the limiter (just after the attenuator) also died. But the damages are less apparent.



P.S: I got the instrument broken and was not responsible for all this. A gorilla probably fed multiple Watt into the poor thing.

Also worth nothing that signal generators suffer from similar problems i.e. idiot users.

In the following example someone clearly connected their radio to the signal generator, which is fine, and keyed down, which is not fine, shoving a few watts up the poot and into the attenuator 



Magic smoke had escaped from the first attenuator step.

I prefer those attenuators to the thin film ones if I'm honest. At least there is some chance of repairing it!

[Robert763]

On SA inputs,
Anything added to the input decreases performance so for high performance analysers they leave protection out. They are playing the datasheet performance specification game. Why degrade their specification and miss the chance of a profitable repair if the operator isn't paying attention. All the big makers sell limiters to put on the front when full performance is not required.

[Kosmic]

New acquisition: Anritsu MS610B spectrum analyzer 10kHz-2GHz

Nice,
BUT 1V RMS is a LOT of input for a SA. It's +13 dBm or 20mW the MAX input for a 610B is 20 dBM (100mW see attached.) This is a bit close for comfort.  If you manually switched the attenuation down you could blow the mixer. Add a 10dB attenuator to your shopping list and keep it on  the SA until you have more experience. Fortunatly the 610B has good DC voltage resistance at 50V. Some SA mixers die with tiny amounts of DC.

YIKES!  almost shit when i read that he was stuffing 1v rms into that poor thing.

my sop is to always keep 20 dB in front of an SA until sure that it is safe to go bareback.  a blown mixer or toasted internal attenuator will ruin your day.  i also have a 10W 60dB atten for use when messing with the output of transverters  (mine are all 5W or less).  others have suggested a dc block too.....not a bad idea.

a good SA is a thing of delicate beauty.   be nice to it.

About that, and not having an SA myself nor knowing much about them.... I always wondered... since it's so easy to blow the front end, and since these instruments cost a tremendous amount of money... it always begged the obvious question : WHY the hell don't SA manufacturers protect their damn front-end in the first place ?!   

Of course I am sure there is an obvious technical reason why that's not possible, and any SA owner knows about it.... but I don't. So please educate me if you have 30 seconds between two refills of your cup of tea/coke/coffee....

From what I see in voltmeters or even the RF front end of pre-scalers in  multi GHz counters, the input is often protected by a couple of diodes that limit the voltage to a defined level. Then a resistor is put in series with the input, so as to limit the current going through the diodes, so as not to blow them, should they be solicited ...
Why can't that be done as well to protect against over voltage / too large signals on a SA ? or a variation o fit, or something else entirely that might be more suitable, I don't know.... SOMETHING !!! 


Thanks.

Yours Truly.

Good SA normally have some protections. For example, the Tek 2794 I was talking about has a limiter in the lower ranges (2GHz and less) to protect the mixer. In the Higher ranges (2GHz to 21GHz) I think the YIG filter (band-pass filter) is protecting a little bit.

Sometimes you also have a dc block but normally up to 8GHz. I think a DC block up to 20GHz is pretty rare. Don't think I seen one.

[Robert763]

More TEA,
I made an offer on a 34401A on ebay and it was accepted. 

Like I need another bench DMM 
It can replace the the 34907A data logger on the bench. I might sell the 34907A.

[AVGresponding]

Is it proper TEA if you make it yourself?

Depends what you mean by "proper".

For me, I would ask: Is it Equipment used for Testing (in any sense)?

Your answer to that would be my answer to your question.

It's theft, isn't it? All Proper TEA is theft 

Well done, you win the prize for the groaniest pun of the day

I've heard these diode paks referred to as a "half-wave bridge"; but of course that's wrong as they do conduct on both sides of the wave.

mnem

I've always thought they were a half-bridge rather than a half-wave bridge, for this very reason.   

As for pheasant, I got put off that fairly early on. My art teacher at school found a very dead one maggot infested on the way to school on his bike, threw it in a sainsburys bag and hung it up in the class room for us to draw and paint under "still life". I can still smell it 30 years later 

YOU WERE LUCKY! Down under, that might have been an Emu!

That gave me a flash back to Rod Hull...

Comedy genius! Sad how he died (fell off his roof trying to adjust his tv aerial, don't think Emu did it).

[med6753]

The bent Type 547.....

I've come up with some solutions to save it which I will implement tomorrow and will provide details.


Stay tuned. 

[mnementh]

*tunes scanner to appropriate EMS frequencies*

mnem

[AVGresponding]

Just read the newsletter from German computer magazine c't:

They've asked their readers what this unit is and what it would be used for in their lab:



BTW: I've already submitted my answer to them and there's no prize to win, so no point in hiding your answers here ...

A 6811B presumably?

If I could afford one I'd use it for cross-checking handheld DMMs against a calibrated bench DMM, or if I was feeling decadent, instead of a variac/dim bulb supply. BD139 would use it to assassinate crapacitors.

[bd139]

More TEA,
I made an offer on a 34401A on ebay and it was accepted. 

Like I need another bench DMM 
It can replace the the 34907A data logger on the bench. I might sell the 34907A.

Urf be careful. Showing signs of display failure 

[capt bullshot]

Just read the newsletter from German computer magazine c't:

They've asked their readers what this unit is and what it would be used for in their lab:



BTW: I've already submitted my answer to them and there's no prize to win, so no point in hiding your answers here ...

A 6811B presumably?

If I could afford one I'd use it for cross-checking handheld DMMs against a calibrated bench DMM, or if I was feeling decadent, instead of a variac/dim bulb supply. BD139 would use it to assassinate crapacitors.

6811, 6812 or 6813 - they look the same, just different output power.

Yep, I'd take one, too ...
But not for checking DMMs, that's what the Fluke 5101 is for. The AC source is rather like a variac on steroids and would make a pretty good companion to the WT1600, especially if you add one or two to the number and reach for a 6814

[tggzzz]

Good SA normally have some protections. For example, the Tek 2794 I was talking about has a limiter in the lower ranges (2GHz and less) to protect the mixer. In the Higher ranges (2GHz to 21GHz) I think the YIG filter (band-pass filter) is protecting a little bit.

Sometimes you also have a dc block but normally up to 8GHz. I think a DC block up to 20GHz is pretty rare. Don't think I seen one.

I have two Minicircuits 10MHz-18GHz DC blocks. There's space inside my Tek 492, so I've semi-permanently installed one inside the case. I have to remember to put the other one on my HP8652 every time I use it.

[Vince]

SA input protection.


Thanks for your replies people.

So in short, it sucks to be a SA....

[tggzzz]

It can replace the the 34907A data logger on the bench. I might sell the 34907A.

Isn't the 34907 a superset of the 34401?

[BU508A]

More TEA,
I made an offer on a 34401A on ebay and it was accepted. 

Like I need another bench DMM 
It can replace the the 34907A data logger on the bench. I might sell the 34907A.

A Keysight with input jacks all in red? I smell some heavy modifications ...
Hope, you'll get a good one. And as bd139 mentioned: check the display, it looks a bit dim.

[capt bullshot]

More TEA,
I made an offer on a 34401A on ebay and it was accepted. 

Like I need another bench DMM 
It can replace the the 34907A data logger on the bench. I might sell the 34907A.

A Keysight with input jacks all in red? I smell some heavy modifications ...
Hope, you'll get a good one. And as bd139 mentioned: check the display, it looks a bit dim.

Not just dim, beware the faintly glowing middle dots

[BU508A]

More TEA,
I made an offer on a 34401A on ebay and it was accepted. 

Like I need another bench DMM 
It can replace the the 34907A data logger on the bench. I might sell the 34907A.

A Keysight with input jacks all in red? I smell some heavy modifications ...
Hope, you'll get a good one. And as bd139 mentioned: check the display, it looks a bit dim.

Not just dim, beware the faintly glowing middle dots

Leaky / defective driver ICs perhaps. Oh dear ...