Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

[TERRA Operative]

I like the Roland TR808 that used rejected faulty transistors, to save costs I guess, but they gave it its distinctive sound.
They picked up a bunch of bad 2SC828-R transistors and characterised them, marking them with a white dot and numbering them 2SC828-RNZ
No more transistors that are faulty in that particular special way means no more TR808 drum machines.


So good luck repairing a busted machine... You can get 2SC828 transistors, but not those 2SC828 transistors..

[mnementh]

   C902 lower right. There's C903 hidden behind that transformer. Must go ASAP.   

That transformer is a common mode choke, part of the mains input filter. 

Yup. You can replace all that mess with a shiny new Schaffner filter. 

mnem
*channeling Pitr today*

Isn't there one of IEC filters right next to it? the board is extra filtering, the 24** series have similar extra filtering.

David

IIRC, at least on my 2230, there was just safety caps or MOVs, no inductor in that IEC inlet. It's been a long time tho.

mnem
 

[factory]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

[med6753]

   C902 lower right. There's C903 hidden behind that transformer. Must go ASAP.   

That transformer is a common mode choke, part of the mains input filter. 

Yup. You can replace all that mess with a shiny new Schaffner filter. 

mnem
*channeling Pitr today*

Isn't there one of IEC filters right next to it? the board is extra filtering, the 24** series have similar extra filtering.

David

Correct. Just like the 24XX.

[mnementh]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

Thank you.

mnem
...for saving the rest of us from this misery. 

[AVGresponding]

The obvious answer is to bulk buy a jellybean equivalent, and re-mark them as TI brand BC183L...   

China have that market cornered already

Solder blob the legs, then you can claim you took them out of a working oscilloscope/counter/sig-gen/etc   

[mnementh]

I'll admit that a large part of my dislike for FM probably had to do with my preferred listening format; classic rock with a smattering of current classic-oid rock.

no matter what city I moved to, the 1-3 stations that carried said format invariably were:

1) far away on the wrong side of town, so
2) usually relatively weak and
c) right next to some shite country/new-age/rage rock/crap music station, so constantly flipping in/out between the two.

When mp3s came out, being able to get away from the constant dropping out and flipping and background hiss was a godsend; I loathed the assache of my CD cartridge changers and was one of the first ripping my collection to CD/R, then they started making aftermarket car audio that played from thumb drives and iPuds and I was in heaven. No hiss, no dropout, and along with that, no fucking commercials or asshole DJs/other talking heads.

Yeah, yeah... inferior sound quality. Compared to vinyl. Compared to FM broadcast...? puh-leeeeze.

I've never looked back.

I pay for my content; I'll consume it as I see fit, not some dickbags at a record label who thinks they should be able to make me pay first for the medium, then for the device to listen to it, then for it again on a pay-for-play business model.

mnem
and then have to put up with crappy reception because they won't pay for the broadcast license with enough wattage to reach me...?  

[mnementh]

I like the Roland TR808 that used rejected faulty transistors, to save costs I guess, but they gave it its distinctive sound.
They picked up a bunch of bad 2SC828-R transistors and characterised them, marking them with a white dot and numbering them 2SC828-RNZ
No more transistors that are faulty in that particular special way means no more TR808 drum machines.


So good luck repairing a busted machine... You can get 2SC828 transistors, but not those 2SC828 transistors..

This is precisely the kind of voodoo I was talking aboot with my "Devil's Advocate Mode" post. There is some tiny grain of truth in all that mumbo-jumbo. It's when people build a belief system around that grain of truth that we lose our minds. 

I dare say that if someone were to take the time and expense to tear apart a working TR808, then properly characterize the 2SC828s in them with our modern TE, that one could find a similar current Chinesium trannysistor, buy oodles of the absolute cheapest of them, and find ones that "fail" similarly.

Bam! New-old TR808s.

mnem
*drops back and punts*

[Specmaster]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

NOooooo FM  around here is pretty good it really is. The only ones that do fade out and get poor sound quality from are the local commercial stations, and that is only because you are approaching the outer edge of their transmission range. The national stations will retune into the nearest and strongest signal for that station and for the most part does it seamlessly.

[bd139]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

Got to agree with mnem here. It's absolute garbage talk or repeating playlists. Don't even get me started on Magic or Classic FM here. I'd rather shoot my ears off.

My entire interest in electronics is a long story but it started in the space of broadcast FM repair. Every bit of electronic gear I had existed only because of that and poverty. It was entirely so I could tape shit off the radio and didn't have to spend money in Woolworths buying LPs and singles.

But due to the rapid commercialisation in the late 1980s, quite frankly, it was a soul sucking state of affairs. Eventually I moved to the numerous excellent London pirate radio stations pushing out jungle and techno. Got involved in one in for a bit (that's one for an off line discussion  ). But after that it was the start of the age of the mp3. Didn't need a radio, could afford mini disc player, didn't need any test gear and interests were focused mostly on beer and floozies so off it went. My job went down the computer route as well.

I have not owned a broadcast radio since other than car radios and none of them have ever been used for that.

But there's a calling towards RF stuff always but from a technical or telemetry side of things. The medium is great but the content is terrible. But you can still play with the medium, and associated test gear, without having to suffer the crap of broadcast radio.

One killer for the magic is that I have a little computer strapped to my arm now which has multiple 2.4GHz radios in it (BT+WiFi), a 5GHz radio (WiFi), a 60GHz radio and multiple GPS receivers. This can actually store and transmit all the music I want to listen to into other BT equipped computers that sit in my ears and I can ask it to play what I want with my voice.  We've come ridiculously far. Someone telling me what to listen to is dead.

But it's still very interesting and open for discovery near the extremes of low power and below the noise floor which is what I'm playing with still. Music, broadcast, screw it.

[Vince]

NIXIE DVM REPAIR

OK I am motivated, well at the moment anywho.

I decided to resume work on fixing my turd of a Nixie DVM, Rochar type A.1335, for those who remember this thing.

IIRC that will be round 3.

Just powered it up and quick test to see if it's still alive since the last time I worked on it... 2 or 3 months ago ? Can't even remember when that was. A while ago.

Well at power up, nothing on the Nixie, all dead.... then after 4 seconds some light coming out of them, partially lit digits, then eventually it all comes back to life and they are all rocking.
Strange that. Maybe some leaky caps somewhere that makes for this progressive wakening. I don't know.

Once all the Nixies were properly woken up and working, I could see what it was doing, and it's not looking good... it was free running again... which then cured itr self after 5 minutes of warming up... yes that very problem that drove nuts last time, and that I thought (?) I had fixed.... it's back 

I don't want to lose my sanity just yet, so I won't be looking into that just now.
Instead, my plan of attack is to work on the defective Nixie board, because  it's perfectly repeatable, does it hot or cold, and I guess is bound to be easier to troubleshoot.
So I will work on that first, to make some progress on this troublesome meter, while at the same time being kinda relaxed, as I guess it should not be too difficult to diagnose and fix...
So, low hanging fruits first, to boost morale !     .... then move on to the more challenging issues...

So what's the problem with that Nixie board ? Well you can see it in the pictures below.
It's the third (starting from the right / LSD) Nixie. It can count only from '0' to '1'. Also, it looks like it fails to overflow, which means it never increments the 4th / last digit next to it, the latter is stuck to displaying '0' as consequence.  Swapped board with the other, working meter to figure that out 100%.

So that will be my first activity on the meter... it's 17h15 I will spend a bit of time this evening on it, and maybe an hour or two every evening after work.
A little bit at a time, hopefully I will eventually make progress and fix the thing.

[Neomys Sapiens]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

[25 CPS]

And for the page:




-Pat

You must get that big iron amplifier in the background up and running and blasting some Dark Side of the Moon. 

That's the WINTER amplifier!  (well, one of them, anyway...)

Dynaco ST-70 clone.  I know I've posted these pics here before, but am doing it again because it's purty when it's all warmed up.


-Pat

This is the VTA clone, right?  I was looking at picking up one of the modern kits but the ones that dynakitparts.com sell have been out of stock for quite a long time.  I'm wondering if that was a one and done production run of kits that aren't being restocked.  VTA redesigned the chassis so it doesn't look like an original ST-70 anymore.  I might drop them an email and ask what stock levels and shipping costs look like.

I never kept a Dynaco ST-70 back in the 90's when I started out when they were cheap and plentiful because I had a pair of Mk IV amplifiers, and that was a big mistake.  I finally corrected that when I was looking at the ad for the Stark resistance and capacitance decade boxes and saw the seller also had an ST-70 for sale.  He gave me a great deal on all three:



We spent a nice afternoon in his garage listening to music and talking about electronics and test equipment (he had an HP 333A distortion analyzer but no sine generator to go with it yet) until I had to leave for work.

[Squarewave]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

Leakacell? I ditched those years ago. They can't make a battery which doesn't leak.

[Neomys Sapiens]

BLEEEEARRRRGHHH!!! Black coffee is for bitter people with dried up little souls. Like Sid. 

You rang. Sitting here drinking the stuff 

Engineers and IT folk exist on the stuff mostly.

Edit: med knows how to coffee like an engineer 

Well, we all know I failed as a professional engineer... so I suppose your record is untarnished. 

But I've done my time in the ivory tower in two different disciplines, and I knew plenty of actual Dilberts and BOFHes, and many of them were of similar mind; the bitter herb is a necessity, that doesn't mean you have to suffer for your addiction and drink it black just because other people say so, like you were a member of *hissss* management or summat.

All y'alls can have my moo sqweezins when you pry them from my cold dead claws. Prolly another 5-10 years at most. 

mnem

Beware the Rindsmilchübersättigungsübelkeit! I drank coffee with cow extract until I could not have gotten down another cup. Since then, 90% black and I'm fine.

[Neomys Sapiens]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

Leakacell? I ditched those years ago. They can't make a battery which doesn't leak.

If I interpret the bit which shines through the white fuzz correctly, Varta.

[AVGresponding]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

Got to agree with mnem here. It's absolute garbage talk or repeating playlists. Don't even get me started on Magic or Classic FM here. I'd rather shoot my ears off.

My entire interest in electronics is a long story but it started in the space of broadcast FM repair. Every bit of electronic gear I had existed only because of that and poverty. It was entirely so I could tape shit off the radio and didn't have to spend money in Woolworths buying LPs and singles.

But due to the rapid commercialisation in the late 1980s, quite frankly, it was a soul sucking state of affairs. Eventually I moved to the numerous excellent London pirate radio stations pushing out jungle and techno. Got involved in one in for a bit (that's one for an off line discussion  ). But after that it was the start of the age of the mp3. Didn't need a radio, could afford mini disc player, didn't need any test gear and interests were focused mostly on beer and floozies so off it went. My job went down the computer route as well.

I have not owned a broadcast radio since other than car radios and none of them have ever been used for that.

But there's a calling towards RF stuff always but from a technical or telemetry side of things. The medium is great but the content is terrible. But you can still play with the medium, and associated test gear, without having to suffer the crap of broadcast radio.

One killer for the magic is that I have a little computer strapped to my arm now which has multiple 2.4GHz radios in it (BT+WiFi), a 5GHz radio (WiFi), a 60GHz radio and multiple GPS receivers. This can actually store and transmit all the music I want to listen to into other BT equipped computers that sit in my ears and I can ask it to play what I want with my voice.  We've come ridiculously far. Someone telling me what to listen to is dead.

But it's still very interesting and open for discovery near the extremes of low power and below the noise floor which is what I'm playing with still. Music, broadcast, screw it.

Someone telling me what to listen to is often how I discover new music.

[AVGresponding]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

This situation is not news. Why are you still using primary cells in something you care about?   

Hope you can get them to replace the thing, no leak guarantee etc blah yadda

[bd139]

BLEEEEARRRRGHHH!!! Black coffee is for bitter people with dried up little souls. Like Sid. 

You rang. Sitting here drinking the stuff 

Engineers and IT folk exist on the stuff mostly.

Edit: med knows how to coffee like an engineer 

Well, we all know I failed as a professional engineer... so I suppose your record is untarnished. 

But I've done my time in the ivory tower in two different disciplines, and I knew plenty of actual Dilberts and BOFHes, and many of them were of similar mind; the bitter herb is a necessity, that doesn't mean you have to suffer for your addiction and drink it black just because other people say so, like you were a member of *hissss* management or summat.

All y'alls can have my moo sqweezins when you pry them from my cold dead claws. Prolly another 5-10 years at most. 

mnem

Beware the Rindsmilchübersättigungsübelkeit! I drank coffee with cow extract until I could not have gotten down another cup. Since then, 90% black and I'm fine.

This is now my favourite German compound word. Suffer badly from it to the point I drink soya milk.

[bd139]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

Got to agree with mnem here. It's absolute garbage talk or repeating playlists. Don't even get me started on Magic or Classic FM here. I'd rather shoot my ears off.

My entire interest in electronics is a long story but it started in the space of broadcast FM repair. Every bit of electronic gear I had existed only because of that and poverty. It was entirely so I could tape shit off the radio and didn't have to spend money in Woolworths buying LPs and singles.

But due to the rapid commercialisation in the late 1980s, quite frankly, it was a soul sucking state of affairs. Eventually I moved to the numerous excellent London pirate radio stations pushing out jungle and techno. Got involved in one in for a bit (that's one for an off line discussion  ). But after that it was the start of the age of the mp3. Didn't need a radio, could afford mini disc player, didn't need any test gear and interests were focused mostly on beer and floozies so off it went. My job went down the computer route as well.

I have not owned a broadcast radio since other than car radios and none of them have ever been used for that.

But there's a calling towards RF stuff always but from a technical or telemetry side of things. The medium is great but the content is terrible. But you can still play with the medium, and associated test gear, without having to suffer the crap of broadcast radio.

One killer for the magic is that I have a little computer strapped to my arm now which has multiple 2.4GHz radios in it (BT+WiFi), a 5GHz radio (WiFi), a 60GHz radio and multiple GPS receivers. This can actually store and transmit all the music I want to listen to into other BT equipped computers that sit in my ears and I can ask it to play what I want with my voice.  We've come ridiculously far. Someone telling me what to listen to is dead.

But it's still very interesting and open for discovery near the extremes of low power and below the noise floor which is what I'm playing with still. Music, broadcast, screw it.

Someone telling me what to listen to is often how I discover new music.

I prefer to be given a menu than served gruel in a loop. Which is commercial radio.

[Cerebus]

Yuck. The coffee has a HP-ish color. 

Call that a cup of coffee? This is a cup of coffee:



If it's not as black as Louis Armstrong in a light-proof room, it's not black enough.

(I really thought that was a cup of builders tea with way too much milk in it, not coffee.)

Well if you like your coffee dark and bitter then Starsucks would be right up your alley. Worst coffee on the planet.

Mellow Colombian with just the right amount of half-and-half. Not whole milk. Doesn't cut it. And no sugar.

I went in a Starbucks once, I haven't been back. Coffee doesn't have to be bitter just because it's strong and black. That's actually made (Americano - double ristretto, 93ºC, 8 bar, 30 seconds, made up to volume with 70ºC water) with 20gm of light roast Colombian Excelso and would surprise you could you taste it - about as unbitter as coffee can be.

[Neomys Sapiens]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

This situation is not news. Why are you still using primary cells in something you care about?   

Hope you can get them to replace the thing, no leak guarantee etc blah yadda

Because at least one of the bloody things has to be kept in a READYNESS state?

[bd139]

Aaaaaaargh! Fuggitt! I just lost another Mini-Maglite to the leakage monster!
 

This situation is not news. Why are you still using primary cells in something you care about?   

Hope you can get them to replace the thing, no leak guarantee etc blah yadda

Because at least one of the bloody things has to be kept in a READYNESS state?

GP ultra AA’s. Never had one leak. One did go open circuit once but that was it.

Interesting we had an exploding llama the other day.  This was a bunch of GP LR44’s in a light up llama toy my youngest had. Went with quite a bang. So don’t buy their LR44’s 

[mansaxel]

FM goes out all of the time as well. It just degrades audio rather than the difficult to recover bitstream. Digital isn’t always the answer is it 

1000x this. fuck broadcast. period.

mnem
 

No, just no  , I wouldn't have a TE problem if I hadn't started collecting equipment, to help repair the broadcast (AM/FM) equipment. Also still listen to both, even if the choice is a little limited these days.

David

Got to agree with mnem here. It's absolute garbage talk or repeating playlists. Don't even get me started on Magic or Classic FM here. I'd rather shoot my ears off.

I'm obviously quite partial, since I've worked at the largest radio company in the country, and currently work at the largest TV company. 

I will object to both mnem and BD, and deem your opinions as too local. The US radio market is crap. Sounds horrible too. The UK market, well, not for fringe music -- never was the alternative except in some rare cases, like that one hour program we sat waiting for all week with the tape recorder cocked.  Radio, since the price per hour is so high, (it being limited to 24h/day) works best for "established" culture. Or the most blatantly commercial. 

I'm quite fond of the culture channel from WDR, for instance. It helps me find and discover culture phenomena I did not know I was interested in. (And yes, WDR I catch by streaming, of course! Except when we passed through this summer, but then only the traffic program, because it is necessary.)

For the observed use cases; AOR and urban dance music, one would do much better with a playlist or a streaming service. Both are "long tail" phenomena, especially so of there's an esoteric streak to ones preferences in either sub-culture.

To keep us on track, and on topic, I'd argue that the FCC and Ofcom have something to answer to regarding quality. Overmodulation is quite the norm in the US, and the frequency plan being so jam-packed as it is, won't help.  Deviation meters have told quite convincingly that most commercial stations go way too high.  The DAB experience, as is, in the UK, is no better. The need, for cost reasons, to keep everything in one multiplex (an E1, i.e 2Mbit ) has pressed bitrates down, so that BBC4 is 64 or 96kbit mono.  We did controlled listening tests that found 192kbit minimum, with a strong preference for 256kbit, before quality was acceptable. At that rate, there's no more than 8 channels in the package, and that's not economically viable.  The only usable expansion for "DAB" is "Dead At Birth". FM rules.

(look at http://www.astra2sat.com/british-radio/uk-digital-radio-bitrates/ which immediately indicates that iPlayer is the preferred medium; probably better than FM even at excellent reception; 320kbit AAC is very hard to distinguish from linear 24-bit, which is what we in Sweden feed our FM transmitters with. )