Dude, I know you work hard to produce these videos, but the lack of video clarity made watching too difficult. It's a big fat BOO from me. Please sort out the focus issue otherwise I will not watch future videos.. Otherwise I love watching your hard work

@CuriousMarc

9 ай бұрын

This video requires expert watching skills! Close your eyes from 1:35 to 2:15. Imagine a 4k picture of a potato instead. Problem fixed! If the focus does not come back after that, change the CRT in your TV.

@johnappleseed6505

9 ай бұрын

@@CuriousMarc Instruction unclear, got my cat to be the first cat on the moon.

@richardhole8429

9 ай бұрын

You are watching for free?

@johanrg70

9 ай бұрын

Oh no! You wont watch again, what a loss! Less than a minute of material was unfocused, and could not be recorded again, totally unforgivable. /s

@fnmatrix

9 ай бұрын

Oh Boo.... 2.6% of the Freely provided video content was blurry. ARG! I'm just never going to watch again! Yeah, whatever dude.

You know it's a good electronics repair video when it involves a drop saw.

@EricLikness

10 ай бұрын

AND the lathe too!

@benjaminhanke79

10 ай бұрын

"Darth Blader" 👍

@jlwilliams

10 ай бұрын

And gears… how many times do you hear of an electronic gizmo that's not working correctly because the gears are out of alignment? And how many technicians (except for CuriousMarc) would know what to do about it?

@ShainAndrews

9 ай бұрын

Chop saw...

@TheDefpom

9 ай бұрын

@@ShainAndrews it is called a drop saw in my country.

Incredibly impressed you managed to avoid breaking the old brittle plastic gear despite the shrinking. Another great repair!

@CuriousMarc

10 ай бұрын

I got lucky that the gear just shrunk but kept some strength. I was ready to machine a new one in metal if it broke on me…

@simontay4851

9 ай бұрын

How do you machine a new metal one. I would like to see a video of how you do it. I always thought gears were cast.

@CuriousMarc

9 ай бұрын

That would have been interesting! You cut the teeth with a divider head and a special gear cutter profile.

@goawayyoutubeplz

9 ай бұрын

@@CuriousMarcor maybe 3D print a new one?

@CuriousMarc

9 ай бұрын

Good thinking, an SLA print with some high strength material would probably work too.

the potato vision bit feels like blown up 1960's tv, perfect 🤣

@pintokitkat

10 ай бұрын

enhanced by the typo of 'papato'.

Working on these microwave mechanics must be nerve-wracking. Another sweet repair! BTW, you should do your own voice-over for the "minutes later" memes. You are among the few creators who could do it authentically.

I've never noticed before that your saw has a logo on it: "DARTH BLADER"

@CuriousMarc

10 ай бұрын

And the mill says Drillenium Falcon. The stickers used to be available from Lincoln Street Woodworks but I don’t see the at the moment: www.etsy.com/shop/LincolnStWoodworks

@Petertronic

10 ай бұрын

@@CuriousMarc They were probably threatened by Lucasfilm/Disney....

I am in awe of your patience and dedication in figuring out these cavity plugins! I mean the dearth of proper calibration documentation and big DO NOT OPEN warnings and specially timed gear-trains all over the place (not just here, but in the Air Computer as well), and yet here we are, with a 0.1% calibrated instrument through careful reverse-engineering, photo-enhanced disassembly, and the all important semi-professional "futz-tuning"! You need to get some proper calibration stickers 😊 I'm sure you have some viewers at NIST who could help you with that 😏

@dustysparks

10 ай бұрын

wink wink... nudge nudge...

@CuriousMarc

9 ай бұрын

Just for you, first merch on my new Fourhtwall store will be very special calibration stickers! Right here: curiousmarc-shop.fourthwall.com . Let me know what you think of their service and quality

It's not potato vision, it's period-correct resolution! (well, at least for television)

It's a total mystery to me why Marc doesn't have at least 500K subscribers. It's a sad indication of the state of education today. Still, on the plus side, the first rule of Marc is you do not talk about Marc. The second rule of Marc is you do not talk about Marc, but dammit, I am going talk to everybody I know about Marc! Btw, nice work with the chop saw. 🙂

The emeritus microwave professor that “snuck” me most of the Nixie tube counters I now have before they went to e-waste, pronounced it “three jiggahertz”. He was an expert who had taught the subject since the 1950’s, so that’s how I will forever pronounce it. He must have come from just after the era of “kilomegacycles”

Bill and Dave's Excellent Adventure! Nice work.

That lathe trimming assured it from breaking when it shrinks even more! Good idea!

@aserta

10 ай бұрын

Unfortunately, it's just a temporary fix, they break even when they're loose. The plastic is just too old. There's a guy who makes various HP gears out of nylon, i forget his name, but i fixed an older probe i got for free.

@cheapasstech

10 ай бұрын

@@aserta shrinkage is what breaks most plastic - even nylon gears - on my old equipment. Sadly not all plastic gears can be replaced with metal ones.

@w9gb

10 ай бұрын

@@aserta Can not remember his name (nylon replacement gears). There was another machinist that makes brass gears for the HP 8640.

Mecanics, electronics, RF, measurements, pure excellence…. Fascinating.

Don't worry about the accidental lowpass filter on the video. I'm here for the expertise, inspiration, and a rare opportunity to learn about equipment most of us rarely see, let alone work on.

Another excellent repair! I just got the boards you designed to fix the HP ECL pulse generator. Waiting for the rest of the parts to arrive from Mouser. Thanks for everything you do!

@CuriousMarc

10 ай бұрын

Great! Let me know if it works for you too.

@derkeksinator17

10 ай бұрын

Ha, I've got an 8008 with a couple of faults, but didn't get around to fix it completely yet.

@vincei4252

9 ай бұрын

@@CuriousMarc Will do!

1964..... that brings back memories..... I moved towards the light and promptly got slapped into reality! It was a good year to take my first breath. 😉 Man, how time flies....

Seeing you try again and again makes me feel admirable. I learned the spirit of never giving up from you. Thank you for allowing me to watch this video

I so enjoy watching you repair this old equipment. Merci bien !

This is something beyond electronics repair. Master.

Marc, Thx for taking the time to make this video. I have almost all the plug-ins for the 5245 counters. I'm only missing the voltmeter. I also have the 18 GHz one too. My approach to these mechs are the same. Wash out all the congealed grease then come back with a synthetic clock oil. The synthetic oil will not congeal like regular greases do. I also have an electric wall clock that suffers the same issue congealed oil. I rolled the price of these counters fwd to today's prices which turned out to be approx. $30,000 the the base 50 MHz and period counter. Then add to that for the plug-ins that you need. Quite a complete system. Imagine having a DVM on your bench in the early 60s. That would be way way ahead of it's time. After having to repair one of these you find they used germanium PNP transistors throughout the crkts. A study of these counters shows you how to make flip-flops and digital logic with just discrete transistors. Marc, how is the extension cable made, connectors that is? The signals go through coax and voltages go through wires.? Thx in advance.

@CuriousMarc

8 ай бұрын

I’m just like you, missing the digital voltmeter. Video on the 18G plugin repair coming soon. Yes the extension cable is made with two centronics/Amphenol connectors, two coaxes (one for clock and one for output signal), rest is regular computer ribbon wire.

Oooo, good morning Mr Marc, and what a good morning this is.

Yes that old grease can get really hard to work with, and old plastic as well.

@CuriousMarc

10 ай бұрын

You bet! And the bearing surfaces being so unusually large makes everything 10x worse!

As an electronic engineer, I marvel at your mechanical dexterity.

I love the gate indicator flashing on beat to the outro song for a while :)

Amazing work Marc. Thanks 👍

Nicely done Doctor Marc! Your channel is one of my go to favourites in the KZreadverse!

Oh thank you for still feeding my intellect during the summer break :), while most others buggered off. I have no idea about microwave, but a step recovery diode in a tunable cavity, to select harmonics to select division factor, is genius ! So simple, so logical, so elegant.

Great video content! Thank you Marc.

Finally! More repairs for Repair God!

I find it immensely enjoyable watching you work, problem solve and fix these wonderful devices.

I could watch these video's for hours. Thank you so much!

Beautiful fix! You can't kill those awesome old HP counters!

It's such a feeling of satisfaction when you return operations to how the original designers made it all this moons ago

Superbly done!

Such beautiful equipment and a great repair! It just goes to prove the old adage that WD40 and a hammer will fix anything ;)

bravo !! ,toujours impressionné par votre travail et par les magnifiques appareil auxquels vous redonnez vie, un grand merci pour le partage c'est a chaque fois un réel plaisir.

Next step, now that this fine instrument is repaired: Calibrating the vintage Apollo era HP microwave oven to make NASA approved popcorn.

These really are fantastic equipments. I have used these in 1969-1971 when I was working in the Finnish Telecommunication Radiolaboratory.

This was wonderful, thanks. The mechanics of the gear train is really fascinating. Think about how that offset gear tooth can stop the rotation of the whole train (before damage to the cavity components by over travel): That tooth collides with a similar tooth on a different gear, but only after the correct number of revolutions. And it all has to be set up to match the frequency range and linearity of the cavity. And it works beautifully after 60 years! Reminds me of the gear train in the Collins R390A.

Another Masterful Repair. What more can I say, great job Marc!

i one thing i have learned here is the importace of accurate test equipment ..very kool to see :)

Another great one, Thanks

I had good experience to dissolve hardened grease from that era with white spirit.

Nice work!

Excellent video

My 5254A has the same problem with the plastic gear which has shrunk. However, I don’t have a lathe to bore out the hole. I’ve considered maybe using a small drum sander on my drill press, but I don’t want to make matters worse. Maybe I’ll get the nerve to go through with the repair, but for now I’ve just reassembled everything and plugged it in to the 5245L to fill in the hole. Thanks, Marc, for showing us the whole process; at least I’m reassured that I’m on the right track.

@CuriousMarc

9 ай бұрын

Drum sander in drill press should work fine, give it a try! I hardly had to shave it in the lathe, just one pass. Alternately you could sand the metal post with sand paper wrapped around it.

@KallePihlajasaari

9 ай бұрын

You could take a shaft and build it up with whatever and then packing tape to close tot he inside diameter, then glue a turn of sand paper to your custom sanding drum and work it slowly in short increments inside the plastic gear.

Instead of placing your plastic gear into the Lathe, I would have FIRST used Boiling water (100°C, 212°F) that would have expanded and slightly softened the plastic gear. Taught by my old high school electronics & physics instructors from early 1970s (Apollo era). ** Used on several restorations - saving big $$ **

Sweet success.

Really amazing work! The folks who make WD-40 also make an excellent penetrating oil. I just completed the repair of an HP 2590A Microwave Frequency Converter that, combined with your counter and HP 5253A plug-in, would allow counting up to 15 GC (GHz for you young ones) plus AM and FM demodulation. Thanks for another great video. Regards, David

These Apollo guys were so smart. Even not wearing pants knowing Marc would meme those decades later. what a foresight.😂

6:18 wow, that must've been _very_ stuck indeed. Your hand was even shaking.

Thx! Great!

Bravo!

They have very similar style gears, although a bit larger, in Yaesu & Kenpro ham radio antenna rotators.

👏👏👏 well done

I wonder if a bit of low level heat would help loosen parts like the plastic gear that was stuck on. Like a hair dryer set on low. Just something that adds a bit of heat without endangering the plastic or other parts.

I like those oldfashioned Vernier buttons :) I have always been fascinated how they could "reduce" the advancing of, say, a tuning capacitor by "forcing" a user to turn the knob many times (18 times in your case !) ... Too bad those mechanical things are such a pain to keep in good working order... It was unclear to me however, if you were trying to set the bandpass filter of the module to let through 10 or 50MHz.... could you clarify next episode please? Merci :)

@CuriousMarc

9 ай бұрын

Both! The clock input starts at 10 MHz, so the first stage needs to be tuned for that. But then there is a x5 multiplier to 50 MHz. So all the stages after that need to be tuned to 50 MHz.

As always, another masterpiece of a video! Does anyone know what music is used in the intro's of this channel? I absolutely love it and would like to know more about it.

@CuriousMarc

9 ай бұрын

It's Festive Dinner by Pony Music.

Putting a blower on the gears will warm things up and allow IPA to seep in even deeper, so you don't have to use pliers. The least you touch gears with pliers, the better IMHO.

@ShainAndrews

9 ай бұрын

Recon we are going to ignore the evaporation factor.

I had racal frequency meter with nixie tubes and discreet electronics. And a 100mhz prescaler. But a spider got inside it and mucked up the electronics

oooo that last gear looked like it had some sort of locktite... not sure i would have removed that! would have rearranged the other gears to get correct alignment! mental note, always mark gear meshing with a solvent-resistant mark *(a scratch!) before removing unknown gears, because i know i am not a savvy as the master marc!

@CuriousMarc

9 ай бұрын

It does look like it, but there was no loctite. It’s just me having added a red marker trace on the shaft, so I’d know at which height to put it back. Turns out that was unnecessary, there was a grove in the shaft for that purpose.

Lovely"

Have you tried to apply heat on stuck parts?

Hi Marc, if you have stuck metal gears it often helps to heat them up a bit (with a small torch or hot air gun). That should cause the gear to expand a little bit and break loose. (And also might help to release any loctite or similar glue that might have been used to fix it onto the shaft).

Does the gate neon never turn off completely? I've got the same unit, but slightly younger, and in mine it does. Maybe they did some changes over the years. As fare as I'm aware, these devices where produced up to the early 70s.

@CuriousMarc

9 ай бұрын

Yes it should turn off. Sometimes it does, sometimes it doesn’t, you can see it happening in the other videos. One more thing I need to fix!

@schmitzvonschmitzen2870

9 ай бұрын

@@CuriousMarc Well, my gate oscillator just broke... no more indicator action on mine as well.🙃

@CuriousMarc

9 ай бұрын

@@schmitzvonschmitzen2870 Maybe a transistor or the neon itself? Let me know what you find!

@schmitzvonschmitzen2870

9 ай бұрын

​@@CuriousMarc There was definitely no gate triggering anymore, not just a broken indicator. Anyway...fixed it for now by working some switches. I guess the Sample Rate- or Holdoff Multivibrator wasn`t working anymore. Either because of the Sample Time pot, which is operated quite frequently, or some other control signal did not make its way to the Gate Control circuitry. Many possible reasons for those multivibrators not to multivibrate anymore. So treat them well, gating is a nice thing to have on these units!

👍👍

I wonder if it would be possible to invent something like an ultrasonic lance, to free components that are completely seized like that? So you apply WD40, then bolt the lance (firmly!) to the shaft, and inject a signal for a couple of hours.

@absurdengineering

8 ай бұрын

There’s fine line between that and ultrasonic welding of plastic. But we won’t know until someone tries it!

If we feed all CuriousMarc videos into ChatGPT (TubeGPT?), will it then be able to generate repair videos for HP stuff Marc hasn't yet been broken or repared, and even fix itself all the HP stuff send to Marc...?

@ydonl

9 ай бұрын

Groan. Real life is SO much better than not real life!

Wooo

Wow

i was expecting you to make a new gear on the lave, not just enlarge it's hole ? shouldn't the gear ratio shift if the part have shrunk ? Or maybe it doesn't matter because it's only for the front display and nothing critical ?

@ferrumignis

10 ай бұрын

A little bit of shrinkage doesn't change the number of teeth on the gear, just reduces the mesh very slightly. There may be a little more backlash in the gear train because of this, but the ratio won't change.

@vlycop7404

10 ай бұрын

@@ferrumignis thank, i'm so bad at this :( I though it was a ratio between inner and outer size, and didn't take the teeth into account

@ferrumignis

10 ай бұрын

@@vlycop7404 If it was a friction drive then the diameter (or equivalently circumference) would absolutely determine the ratio, but gears are constrained by tooth count. In my experience polymer gears often _expand_ slightly with age due to moisture absorption and sometimes due to to the lubricants used. This can actually increase the outer diameter and reduce the inner diameter at the same time, and sometimes the resulting stress will cause the gear to crack. Super lucky this one was was salvageable as it would have been a quite a bit more work to cut a new gear.

Why did I get rid of my 5245?!

For what it's worth I couldn't tell it was fuzzy, because my phone is a potato

Can I like, come and hang out with you guys?

If I had anything to add this comment it would be gold!

An electronics expert once told me that everything above 100MHz is basically black magic.

DO NOT use WD-40 as a permanent lubricant. It will solidify leaving you in the same position you started with. Clean all WD-40 out and replace it with a proper lubricant.

@ShainAndrews

9 ай бұрын

LOL. WD-40 "solidifying". Hilarious.

@randycarter2001

9 ай бұрын

@@ShainAndrews WD stands for water displacing compound. It's not a lubricant. It seems oily but is does dry out and solidify.

Not 10th!

300th!

@CuriousMarc

10 ай бұрын

Oh, you did much better. You are 6th. That's still pretty fast by my count. Deserves a free out of tune resonant cavity.

@dustysparks

10 ай бұрын

KZread doesn't really show anything below 300 anymore I've noticed. So 1 to 300 = 300

Fifth!

@CuriousMarc

10 ай бұрын

Yes, right on, fifth! Special award for getting the actual count right!

First!

@CuriousMarc

10 ай бұрын

4th says KZread. That still count as pretty fast. Your free plugin might be slightly out of tune though.

First View:)

@CuriousMarc

10 ай бұрын

Second! Your still get awarded a free plugin, but only to 500 MHz.

First!

@CuriousMarc

10 ай бұрын

KZread declares you the first first! You get a free plugin upgrade to 3 GHz.