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- Опубліковано 12 вер 2024
- Well, repair-ish. Fixing the adjustment issue in the Systron Donner oven crystal oscillator. More issues found though.
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I really like the positivity as of late ;)
I've left with a smile and having learned a thing or two for a few uploads in a row. Much appreciated. Thanks Dave.
How to use a frequency counter as a gravity detector: Drop it. If it falls, then yep, there's gravity.
My phone also work as gravity detector.
Still Render Production Yes but only once or twice depending how durable your phone is.
@@vgamesx1 You correct , I try trow my phone up it fly away and never drop back,I guess no gravity here.
Still Render Production Actually, most phones contain a built-in gravity detector. It's used to determine the proper rotation of the screen image. With a test application you can see the numbers it outputs.
Also how to determine the age of one of these. The bigger the crater it leaves... :D
nobody sees the broken resistance near pin 14 of the IC ?? 7:31
Oh, didn't see that.
Well spotted, that resistor has sheared in half which can't be good.
And the board is burnt there. Something not quite right. Com'on Dave, fix the beastie. It's begging for a new lease of life and a new home. Make it a door prize with reciever cost shipping.
Good eye fellow watcher! It's too easy to look over stuff when filming, too bad for the creation and viewing delays!
I was also wondering why Dave didn't spot that. ;-) It's very obvious and a common mode of failure for these things.
OCXO's require a minimum of ten minutes of warm up when they are working. Tantalum capacitors are a type of electrolytic capacitor. You cannot replace them with non polarized Mylar film capacitors. Tantalums are usaually very accurate as to their ratings unlike a standard electrolytic and used in precision circuits.Try finding a tantalum of equal value for precise calibration or substitute an electrolytic if precision is not of importance. Not much can go wrong with these units unless the heater element has gone open circuit. Love your videos and the great commentary! CHEERS!
I don't know what stability tricks the new ovenized oscillators have implemented, but an ovenized oscillator that has been running for years is noticeably more stable than it was when it was new. The internal mechanical stresses have stabilized over the years, reducing drift components. In other words, and old one is better than a new one, and one that's been running for 20 years is best.
I really enjoy your repair(-ish) videos. You have a good way of showing how to understand a circuit and find the failure.
And it seems you videos in general have been more positive as of lately. It really suits you and your channel!
B 1:49 😅
😊k😮 4:49 😢 4:50 😮😅😮
Fix the heater dave, have patience for the old beast, loverly old counter.
I agree, fix it! Get the heater heatin' and trim its frequency against the modern one.
Or give it to someone else.
Atleast its from an era where service personnel were expected to solder and the manual actually tells you everything you need to know if not more.
Can't find a manual for this, it could be interesting.
I'm sure the manual for this is on some micro-fiche somewhere in a dusty old file cabinet.
So this is a 1970's Australian designed and built device? Then where is the beer holder and ashtray attachments?
And it must be operated with a fast bowlers mustache.
You forgot the meat pie....
And you forgot the name of the man that designed it. He was probably called Bruce.
Simon Tay,
Ha ha that's made me grin :-D
Dont forget Sheila his wife :)
Well why else is there mold got cover in alcohol and beer while in use lol
I had the same problems with old worn out temperature controlled oscillators, to remove the case I find it better to use a hot heat plate and carefuly use a small gas soldering iron & stanley blades to go between the bottom of the soldered area, suck off as much solder as you can, use flux make the solder run down to one spot, as long as the main case is hot the gas soldering iron should work, I tried this on a Truetime GPS XL-DC 10MHz oscillator, must admit its not easy takes ages to remove the base depends on how much solder you can get off...
I just took out my systron donner 7014 1970 year. Made in USA Concord California.
Been sitting a few years unpowered, so powered it up to prevent decay.
Small ac fans were used such as boxer or muffin fans.
Typically heavy rotors, sort of like my Revox reel motors.
Spins really freely by hand, probabaly lubed by my test and measurement repair team.
Takes a bit to spin up, but totally free spinning.
Some friends would say when is it going to take off?
A few years ago I took it back from storage hoping it was not tossed. It was my instrument, and was going to be used in a reflex timing exhibit.
Got dragged to Maine following new wife's job.
So refreshing to see real 5's rather than upside down 2's. All nice and bright.
Working, more or less, not reassembled properly, I'd call this a professional fix.
Is it actually fixed? the frequency was dropping on it's own from temperature, sure the adjustment pot actually did something, and wasn't just it warming up? :/
The heater isn't working
Freq dropped all time. Not sure did adjustment do anything or not. Can you adjust it up while "natural" dropping? ie. adjust in both directions independently whatever that sick puppy is going by itself.
and of course it was a god damn tantalum
And a tag tant to boot, old school fail.
What are you moaning about, old tantalums make life interesting ! They make an awesome mess when they fail.
right?
Bet all it does is decouple the 5V rail there on the oscillator, and the resistor being super toasty is because it is making the 5v rail from the 30VDc input voltage. Probably the main 115VAC heater is open circuit, and funny enough I have a crystal oven that has the same type of setup, 115VAC heater and a bimetallic thermostat. Was thinking to retrofit it to be somewhat safer, seeing as the heater pins are so close to the oscillator ones, and i am not to keen on having mains voltages so close to troubleshooting the oscillator, even though it does have room to hold 6 crystals in there.
Jorno yep, as soon as I saw that I cracked up laughing.
The tantalum shorting is probably what caused the resistor to get hot
Dave, if you have no further need for this Systron-Donner freq counter and feel like donating it to a worthy cause, I could take it off your hands. The nixie tube display alone would make a welcome edition to my struggling vintage electronics repair shoppe...
Not asbestos, it would be white and very flaky in its raw form and would probably have been wrapped. That looks like glass wool insulation. Please take the "Recycle Rate" control (gate delay) off of infinity so the poor gate circuit can do its job... Also, consider donating it to somebody new, in its day that counter was considered the ducks cuts - I used one like it for many years.
The Recycle rate control barely does it's job. useless on fast, too slow on slow.
Glass wool ,I seen them in very large oven.
I don't think you have repaired it... you found a failed component and replaced it, but after that the frequency was still off and not well reacting to the trimmer. The frequency dropped, but it continued to drop without you touching the trimmer. That is because of the oven heating up (thermal coefficient of the oscillator as a whole is usually negative).
Furthermore, the failure of the tantalum 2.2u capacitor which likely is some supply decoupling in the heating circuit would not at all explain why the trimmer was ineffective.
There must be some other fault like a break in the connection between the trimmer and the oscillator circuit, or failure of another (small ceramic) cap in the oscillator.
little old Oscillator from Pasadena
Lots and lots of flux helps when unsoldering surfaces like that can. The rest of the electronics are magic to me. That's why I watch Mr. Jones do it.
Dave, maybe you've already done one, but I'd like to see a video with guidelines etc--from an industry standpoint--on how you would decide some piece of equipment is beyond economical repair. Obviously the criteria are going to be different than when you're making videos for entertainment/education, but I've had repair requests rejected for equipment that I didn't understand (although of course that usually meant getting brand new gear so I never cry too much.) I was just wondering when it stops being an engineering decision and is just a beancounter decision. Another great video, thanks.
Oh I remember those. Wow, it’s been a looooong time.
I,d like to see it repaired, may not cost much except time.
If its too to throw, fix it. Someone may want to relieve you of it for some cabbage.
I guess I,m old skool. BTW, love your channel.
Cheers, Mick.
WOAH! That's not Pasadena, that's South Pasadena! Yes, located South of Pasadena (and yes, I had to explain this to a lot of people when asked where I grew up.) Really fantastic town if you can afford to live in it anymore. If you ever get a chance to visit and meet the people that have been around for a while you'll understand why I call it a town and not a city.
It's "flapping around" because fiberglass laminate burnt to charcoal and it's resistance is changed due some current flow throught the burnt fiberglass laminate. As I think. Need to replace that piece of burnt fiberglass laminate with new one.
btw, an un-official but very good test for asbestos is to try and burn it (simply put your lighter on it).
If burns or melts you're good, but if it glows hot red without cringing it's the real deal (asbestos).
if you'er not interested in repairing it Dave, and it's destined for the tip... I'm in Brisbane and don't have a stand alone freq counter. I'd be happy to pay the postage and give the old girl a new home!
Multimeter needs a new battery :D
Is that a resistor dropper circuit for the heater? Well, there you go.
@8:50 looks like there is a component broken in two just above the chip on the top left just right of the resistor going over the chip, that might be why its not heating correctly? idk if it's the problem but its work a shot to see if you can get her up and going! Cheers mate
Indeed. That and the damage on the corresponding pad on the reverse side of the PCB immediately stood out.
You're right, there looks to be a vertically-mounted resistor broken in half.
Even though replacing the OCXO with a new one would be easier, i would've still attempted to fully repair the original because its not being wasted then and a new OCXO costs money. Replace the tantalum, check the resistance of the heating coil and check for presence of 115VAC.
Those Nixie tubes are more valuable than the whole counter. Have you seen the price of them, on eBay, lately?
So like the output of this box is a square wave or that sort of thing? So if the crystal is the square source? Does something have to digitally scale that pulse to some other length as per the trimmer? Maybe it just changes the temp of the box, that would work maybe if the crystal was almost bang on to start with.
Yes, the output will either be a square wave, or a sine wave. The trimmer cap pulls the frequency of the crystal to give a small bit of adjustment range. It doesn't change the temp of the box. It would take you 3 weeks to dial it in if it did. And on these old OCXOs, the problem is always, always the heater.
Welwyn is pronounced "well-in" - only 20 miles from my hometown in the UK.
I knew a few guys that worked there in the late 80s. The brand still exists today - now part of the TT Electronics group. They were famous for good quality high power wirewound resistors as well as other wound components.
Turning the 'Recycle Rate' knob from its off/infinity mark may have saved you all that reset button pressing.
That's fiberglass insulation, asbestos fibers are typically more coarse and brittle.
On old OCXOs, it's always the heater.
For many people, this might still be a nice piece of equipment. Do you ever sell these dumpster dive stuff?
"It's got a big strap-on there"
*hyphen added for clarity - obviously.
Trump is advertising on your channel in the states.
LOL, someone screen capture and post a link please!
From the guy always trying to buy broken stuff that comes working won't even fix the little heater circuit
I like the troubleshooting and repair videos. Also there's a lot of different fanboys out there I've come to realize. Thanks for the videos. Love your channel.
I noticed on the other video unpopulated holes for another nixie driver and valve.
If you remove the carbonised parts of the PCBs you'll probably get a greater range of adjustment with the trimmer.
Awesome Video!
I could have unsoldered that no worries done this before on metal cases !
Mine got pushed off of the bench and detected gravity very very well!
Capac-it-tator is my new favorite word.
screw adjustable OCXOs require tongue at the *left* angle
Would atmosphere pressure change the crystal frequency ?
Sweet i was wanting to see this
3:32 OCXO can says "Freq 1.000 MHz" measures at 10 MHz? Maybe the 5313A has a x10 programmed in somewhere?
Oh, missed that. But it outputs 10MHz, the 5313A isn't wrong.
Is there a reason to even use tantalums anymore since ceramics have made so much progress?
The Dollar Guy I'm unsure what rare minerals are used in the higher capacity ceramic capacitors like 2μ2 SMD caps.
I have 10uF ceramic chip capacitors. I believe the layers are so thin from modern fabrication methods, ceramics can reach high values...22uF even. Ceramic capacitors have low ESR and should be the modern and superior equivalent?
Yes, there is such a thing as too low an ESR in some applications leading to unwanted oscillation (ceramics have very high Q and thus poor damping), so tantalum are still useful when you need a lot of capacitance in a small space but do not want either the very low ESR of ceramic capacitors nor the wide swing in capacitance (e.g. -20% to +80%)that comes with higher value (non NP0) multilayer ceramic capacitors.
Monitor PC from South Pasadena, California. I wonder if they're connected to NASA, JPL, Raytheon, Northrop Grumman or some other company in that area in that era. It is not an easy company name to Google search....
nice nixie display
I'd put a solid electrolytic in there like an OS-CON.
sill waiting on a review of that Agilent U1733C LCR-meter
Look at those cute little Nixie tubes!!!
Tantaullum ofc...
My entire house has asbestos siding on it.
Adjusting the 10 MHz, then removed the 1.000 MHz OCXO. ("1.000 MHz" marking most visible at 3m39s).
7:34 I might be wrong, but this pronunciation of "capacitor" reminds me somehow of RODALCO2007, a channel about watt-hour meters and stuff like that. :)
The insulation is actually hair from the gray-bearded virgins.
Why am I even watching this? I spend all day at work fixing OCXO's. And it's Oven-Controlled Crystal Oscillator, btw. :-(
oh, looks like Dave is diving into another motherboard VRM, rrrrrr OCXO thermal solution, lol.
Grabs a snack and a drink, these are good vids. B)
Diddly-Squat, TaDa - thing of beauty, Joy Forever, Get Medievil, Stubburn as a Mule, Right up the clacker, In like Flynn, All the way with LBJ, Winner-winner chicken dinner, Flapping in the breeze: ----- Came for my dose of OzSpeak but you've mixed some American slang in there Dave!
Seeing that screw on the Agilent sticking out was really annoying ;)
Pretty sure that's not Asbestos, more like fiberglass.
Ha, ha, beautiful! Straight-up 7400 TTL quad NAND gate - haven‘t seen one of those in awhile! I guess HC-series (or F-series) TTL hadn’t come out yet. None of this LS rubbish! 😁 And why do they need a heater? That resistor clearly gets plenty hot! Besides, I saw a cheap-as-dirt 1 Megohm 10% carbon comp resistor in there; what gives with that? They want the stability of an OCXO, and they throw in a cheap resistor? What’s next, ceramic disk caps? 😆
this is actually OCXO, not TCXO. OCXO has oven, TCXO has not - it is simply temperature compensated.
Atleast it wasn't welded shut.
Can anyone point me to wiring diagrams for these units? I have a couple and can't figure out the pin outs. Any examples would be helpful. Thanks.
That canned meat is quite weird.
Early Spam. They were trying to prove to the military that it had a long stable shelf life. ;)
Spam in a can!
I concur
Why does the Agilent have a label saying "Damage Lvl" on it? Is this video games?
keep the nixie's and make a clock with a stopwatch
does anyone know why they used to design PCBs without straight tracks, since nowadays industry convention is straight line tracks?
Just something I've noticed.
Back then PCBs were laid out by hand using black crêpe tape on polyester film - no CAD. Doing straight tracks with mitres took a lot more effort than using curves so that 's what you did.
Can you replace it with modern temperature-compensated XT osc?
Sure, or just feed in external reference.
он был разобран весьма не аккуратно ?
gotta lube up that fan's bearing
K-Y?
Yeah, she's probably gummed up at this point (or dry), not a real surprise after 45 years. Better fix that before you get some shorted turns in there.
FIX the old crap. it is good practice to restore old stuff back to working condition
Gotta love swiss tools!
Osc. can says 1.000 MHz ??
Save your tantalum caps for somebody that wants to recover the tantalum from them. Over a lifetime, you could recover up to $100 dollars worth of metal.
=-( sad face for not fixing it properly. More retro videos needed =-)
Couldn't take it off your hands Dave, ill restore it back to health?
9:43 Back to the Future Reference.
Yeah, imagine if they had put an aluminum electrolytic cap there next to the super hot resistor - one day... >bang!< and there goes the whole kit! Oops.
Nah, that's fiberglass, itchy but not deadly unless you inhale a bunch.
Is it just me or does it look like that was reworked from the original design, or maybe repaired before to bridge around the burn? Ah, just wrap it aluminium tape! ;D Oh, no heat to hold in, welp!
Fiberglass, not asbestos.
Being December of 73 I would say no it is not asbestos.
Eh. Asbestos was just starting to be banned for insulation in 73 so its possible.
@@DoRC What other than insulation was asbestos used for?
@@wheelitzr2 I know it was used in brakes and clutches but I was referring to house insulation. Not sure what else it was used in beyond that.
It was also used also in insulating pipes eg. cast iron steam pipes.
That stuff in the can looked like fibreglass though...
- Eddy
@@DoRC you are correct they used it in clutches and brake pads but used as an insulator for the glue backing off the pads, it was Incorporated into the pad material to add insulation from the face to the glued side of the pad or clutch. That's why pads will tend to separate when they get to low due to the heat effecting the glue backing.
Dave, you have a screw loose!!!
Aussie lator you say?
Hair stands on ends, epppps. on the CRACKING open..
Didn't fix it ; not a repair
You're surprised?
But it's still an OCXO, but not a TCXO.
Not if the oven is broken it isn't
It's just an XO now!
Great
Looks like glass fiber to me
rip uniqueness, everyone is copying AvE's language lately...
👍👍👍👍