Author Topic: Test Equipment Anonymous (TEA) group therapy thread (Read 18839435 times)

GreyWoolfe · « **Reply #35900 on:** July 30, 2019, 08:06:28 pm »

Happy birthday, mnem. May you have many more.

mnementh · « **Reply #35901 on:** July 30, 2019, 08:18:10 pm »

Not near enough candles on either of those cakes... THANK YOU for that!!!

mnem
"We tried to do a traditional birthday cake but the Fire Marshall refused to approve the event due to candle count. I believe his exact words were "Disaster just waiting to happen..."

mnementh · « **Reply #35902 on:** July 30, 2019, 08:45:01 pm »

Quote from: BU508A on July 30, 2019, 06:48:12 pm

Quote from: mnementh on July 30, 2019, 04:13:12 pm
It's orificial. 50-something orbits of this ball of mud have occurred under my feet as of today. In that time I've seen everything from crystal radios to proof of quantum entanglement; from the birth of the information age to the inevitability of the disinformation age, from the fall of the Berlin Wall to children being murdered for cellphones. It's been a helluva ride.

Let's see what happens in the next 50.

mnem
Everybody needs something to believe in; I believe I'm going to eat myself a pie.

Hey mnem,

since I'm not the brightest candle on the (birthday) cake, it took a little longer to realize, that today is your birthday.

Congrats to that!

If I would have your address, you'd probably received this:

Oh, sorry! Wrong t-shirt. Here we go:

And, a birthday is not complete without a birthday tune.
But, since nearly everybody is singing "Happy Birthday", here is a "Ständchen" from Germany.
Let me know if you want a (bad) translation.

All the best,

Mounty

I love them both, but I'm a huge sweaty old reprobate so white shirts don't get along with me anymore.

Thanks for the lovely Birthday Serenade! Reminds me of high-school years hanging out around the Duquesne-West Mifflin area of Pittsburgh; lots of old-world flavor there. There was this little hofbrau that made the BEST corned beef on dark salted pumpernickel... *sigh* As you might imagine, that abomination of post-industrial predatory marketeering known as Oktöberfest was very big in the region.

Not like they needed an excuse to get hammered.

mnem
"Does Hagar drink to excess?"
"He'll drink to ANYTHING..."
"Here's tooya, doorknob..."

VK5RC · « **Reply #35903 on:** July 30, 2019, 09:05:03 pm »

@mnem - happy birthday!
May your flame never extinguish!
Don't the years seem to accelerate past!
Rob

tautech · « **Reply #35904 on:** July 30, 2019, 09:13:09 pm »

Quote from: VK5RC on July 30, 2019, 09:05:03 pm

@mnem - happy birthday!
May your flame never extinguish!
Don't the years seem to accelerate past!
Rob

Yep.
50 to 60 seems just 4 years.

mnementh · « **Reply #35905 on:** July 30, 2019, 09:17:57 pm »

Now that I've sold my old electric range (which has paid for the parts to build my new PC), I'm currently taking my birthday off to do what I want to do... which at this moment means the whole afternoon puttering around on my new PC getting it ready for when the 3700x CPU arrives.

This pleases me very much.

mnem
*putter....putter... tinker-putter...*

tautech · « **Reply #35906 on:** July 30, 2019, 09:21:01 pm »

How to you prevent dwagon claws from getting stuck between keyboard keys ?

beanflying · « **Reply #35907 on:** July 30, 2019, 09:47:41 pm »

Congratulations Mnem it's not that scary this side of 50

med6753 · « **Reply #35908 on:** July 30, 2019, 09:50:01 pm »

More work on the Heath OL-1 Scope.

The DC filament supply is complete and running. I used an LM350T adjustable regulator and set it to 6.3VDC. The only issue is I may have to increase the size of the heatsink. It does get rather warm...in fact...too hot to touch. We'll see....that regulator does have overheat shutdown built in. And can the comments about the long screw attaching the regulator to the heatsink. My stock of small hardware is limited. I'll get the correct size tomorrow.

Results.....dramatic. Much improved vertical response and much cleaner trace. Much more stable sync too. Building up that filament supply was worth the effort. There is just a VERY SMALL amount of 120Hz ripple on the trace which I'm going to track down. It's probably normal for this scope because the B+ design is pretty lame. But if I can minimize it with additional filtering and not blow out the 6X4 rectifier I'll give a go.

bd139 · « **Reply #35909 on:** July 30, 2019, 09:58:30 pm »

Looking good. Better luck with your Griefkit than mine.

Turns out the 12AU7 tube in mine is fucked and most of the resistors are out. I can't be bothered to buy one as the Chinese ones on RS are £9 a go so I spent an hour in LTspice and came up with a "solid state conversion" which I am considering doing. Will run cold on a 9v 1nd 1.5v battery.

Linearity isn't bad. Not perfect (~0.3%) but certainly good enough.

Now working on the 6AL5 replacement circuit. Digging through some old PDFs for tube data. Can't just throw a couple of diodes in there. Although the cal sucks on it so that might actually work.

Also need to think about input protection. Tubes just go "meh" and carry on. FETs go "FET!!!" and die. Couple of back to back 3.6V zeners should do it with the series 3.3 meg resistor

Neomys Sapiens · « **Reply #35910 on:** July 30, 2019, 10:02:26 pm »

Quote from: Specmaster on July 30, 2019, 11:19:49 am

Never before have I seen salt, coffee and alcohol given as food groups, wishful thinking I think on the last 2, salt can be a killer.

Yes, maybe. But how comes you know it? The problem isn't so much the processing on the lathe than the tempering to heal out any structural discontinuities in the crystal. It won't survive the launch otherwise.

Neomys Sapiens · « **Reply #35911 on:** July 30, 2019, 10:06:40 pm »

@mnem:
would that not rather be a hatching day?

Royal Armouries got you covered:

med6753 · « **Reply #35912 on:** July 30, 2019, 10:11:11 pm »

Quote from: bd139 on July 30, 2019, 09:58:30 pm

Looking good. Better luck with your Griefkit than mine.

Turns out the 12AU7 tube in mine is fucked and most of the resistors are out. I can't be bothered to buy one as the Chinese ones on RS are £9 a go so I spent an hour in LTspice and came up with a "solid state conversion" which I am considering doing. Will run cold on a 9v 1nd 1.5v battery.

GE and RCA 12AU7's are a dime a dozen on Ebay over here. I don't suppose there's many of them in the UK. And Mullard's are pricey because audiophools prefer them. I would guess they are pricey over there too.

bd139 · « **Reply #35913 on:** July 30, 2019, 10:18:36 pm »

Yeah they're really expensive here. Even the Philips / ex military CV numbered ones are bloody expensive. Cheapest NOS one is £12.50. The audio lot have gone bonkers for the damn Mullard ones. I have considered getting into the market but you need a decent tube tester and they are proper £££ here which puts my cheap ass off everything.

I have however got a metric ton of 2N3819 JFETs so I figured I haven't done a solid state conversion before so why the hell not?

On the matter of tubes, this turned up on ebay here: https://www.ebay.co.uk/itm/362703413572 ... wondering if I should try and save it before it is pillaged!

Neomys Sapiens · « **Reply #35914 on:** July 30, 2019, 10:19:04 pm »

My answer to Bitseeker's question about good coaxial adaptors - slightly revised:

Without blame:
Huber&Suhner, Rosenberger, Radiall, Spinner, Kings, Amphenol RF, Pasternack, Automatic Connector, Southwest Microwave, Delta Electronics Mfg., Trumpeter, Midisco

Former Brands/Makers: Sealectro, Omni Spectra, Astrolab(now H&S), Siemens

Telegärtner, TE interconnect, Pomona, JyeBao only for uncritical applications
Former ones: Greenpar, WiSi

No idea how good Coaxicom, Anoison, Genex.it, Coaxsol (short for Coaxial Solutions), are.

xrunner · « **Reply #35915 on:** July 30, 2019, 10:43:54 pm »

Repairing a ham friend's Yeasu FT-991. Has one bad output PA amp (RD100HHF1) on the HF PA deck. Seems to be the same issue as reported by many others - this device was not set up properly from factory (too high idle current). Ordered two new ones as requested by the customer.

Will also check a few other items in the service manual while it's here.

bd139 · « **Reply #35916 on:** July 30, 2019, 11:10:56 pm »

Very common problem indeed. Last time I was in my local radio shop there was someone in there booking in an FT-950 with the same problem! Blamed it on user error of course but the customer wasn’t convinced.

Having blown the shit out of numerous IRF MOSFETs it has always been bias and temperature instability which should have been designed and calibrated out.

bitseeker · « **Reply #35917 on:** July 30, 2019, 11:35:24 pm »

Quote from: Neomys Sapiens on July 30, 2019, 10:19:04 pm

My answer to Bitseeker's question about good coaxial adaptors - slightly revised:

Without blame:
Huber&Suhner, Rosenberger, Radiall, Spinner, Kings, Amphenol RF, Pasternack, Automatic Connector, Southwest Microwave, Delta Electronics Mfg., Trumpeter, Midisco

Former Brands/Makers: Sealectro, Omni Spectra, Astrolab(now H&S), Siemens

Telegärtner, TE interconnect, Pomona, JyeBao only for uncritical applications
Former ones: Greenpar, WiSi

No idea how good Coaxicom, Anoison, Genex.it, Coaxsol (short for Coaxial Solutions), are.

Thanks, NS! Added your post to the POI.

During my searches thus far, I also ran across some MACOM (M/A-COM) brand. Don't know much about them. Some packaging I saw indicated it's owned by AMP.

bitseeker · « **Reply #35918 on:** July 30, 2019, 11:37:52 pm »

Happy birthday, mnem!

Test Equipment Anonymous (TEA) group therapy thread

Kosmic · « **Reply #35919 on:** July 31, 2019, 12:32:23 am »

Happy Anniversary mnem !

neo · « **Reply #35920 on:** July 31, 2019, 12:36:47 am »

Happy birthday mnementh, wish i had some creative quote or picture of a dragon or something similarly amusing. But I don't, and I'm late to the party already so here is an old stalwart https://youtu.be/EqolSvoWNck?t=102

Formatting is hard.

MaxFrister · « **Reply #35921 on:** July 31, 2019, 12:59:56 am »

Once owned by Kierkegaard:

Ebay title:
HP 606A Rack Mounted / Existential Signal Generator Power Up

eBay auction: #352737876458

Mr. Scram · « **Reply #35922 on:** July 31, 2019, 01:02:20 am »

Quote from: MaxFrister on July 31, 2019, 12:59:56 am

Once owned by Kierkegaard:

Ebay title:
HP 606A Rack Mounted / Existential Signal Generator Power Up

eBay auction: #352737876458

There's an "item not as described" if I ever saw one. "I bought this huge pile of metal and I'm still empty inside"

bitseeker · « **Reply #35923 on:** July 31, 2019, 01:39:52 am »

But you'll feel better for a limited period of time since it's a "power up".

Brumby · « **Reply #35924 on:** July 31, 2019, 01:53:50 am »

Happy Birthday Mnem!

If you thought the first 50 took a long time to roll by - don't worry. The next 50 will only take a third as long!


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Author Topic: Test Equipment Anonymous (TEA) group therapy thread (Read 18839435 times)

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