Lets see your Nixie Tube equipment

[bitseeker]

You snagged that one, Rob?!?      Congrats!!  That's a cool old beast.  I now have a pretty basket-case looking 522B on its way to me.

I look forward to seeing pics of your 521!

-Pat

Congrats, Rob. I, too, look forward to seeing more of the 521.

[Enigma-man]

Long time no see.
Today's show and tell is a General Radio Model 1192-B six digit frequency counter.  The specs say it will measure up to 32MHz, but this one topped out at 60MHz.
The front panel shows 50MHz max.  The manual is for the first version 1192 model from 1969.  The parts and layout are identical.  Perhaps hand picked 7490's were used to make the claim
of 50Mhz.  Not bad for a forty-four year old with 7400 series chips.   The way you see it is the way I got it.  My buddy was hunting for something and found this in a sealed plastic bag.
He said, "Here, Den... Take this frequency counter..."   After much arm twisting, kicking, screaming and fitted with a cast due to the relentless arm twisting, I gave in.
Almost as pristene as the HP counter I showed you a few months back.  It was repaired somewhere along the line by someone who knew what he or she was doing.  No
PC board damage and solder flux cleaned up.  A true sign of someone who takes care in what they do.  Anyway, it powered up okay and zeroed out.  There is a 100KHz test
button on the front panel.  It read exactly that when on the 10 sec gate time.  One picture shows the display on the 1 sec gate time.
Originally it had six digits.  After opening it up, I saw standard 7490 counters and other TTL devices.  I had a display driver and storage IC, but not the miniature Nixie that were
inside.  I compared a standard Burroughs Nixie to the mini one and found the two to be identical except for the glass envelope.  I unsoldered  the socket for digit seven and seated
the one I had on hand.  You cannot tell the difference. In future if one of the mini ones craps out, a standard one can be subbed once the socket is removed.  Maybe not 100% original
but what would one do if you could not find a mini one ?  Eventually all Nixies will die...
The other minor repair was the filter cap for the 5 Volt line.  It is mounted with screws and you cannot slap anything in there.  It had to be the right height.  Shorter is okay, taller is not.
I had only one which fit the bill.  10,000uF at 25 volts.  The original was a 15 Volt, but so what ?
The other mod was removing underrated diodes that had started to burn the pc board.  I put in a 5 Amp bridge and used the chassis as a heat sink.
The time base is a bit odd.  A 5MHz crystal is used along with a frequency doubler, then divided down to get your various timebase values.  It would be very easy
to put in a 10.0000 MHz oscillator module along with a 74LS390 dual decade counter if and when the timebase fails.

[Enigma-man]

Not exactly a Nixie device, but still a cold cathode device are the Dekatrons (GC10B/S) 4KHz maximum frequency rate decade counter tubes.  These are the grandfathers
of display devices.  I downloaded the Ericsson design manual from Deiter's site.  The extensive manual shows how to make actual frequency dividers.  I hope to make a frequency
counter out of the tubes.  Some have blown away zero cathodes from displaying zero all the time, but those can be used as reverse Dekatron spinners spinning counter clockwise.
Aussies will enjoy this because water going down the drain goes in reverse compared to us Northern Hemisphere people.
The tubes need 450 Volts DC. Hooking up to a computer such as an Arduino, Raspberry or any other computer is a piece of cake.  All timing is done in software and no big deal.
My counter will use discrete components and interfaced by optoelectric means.  There is a section in the manual that touched on this using photodiodes/transistors.  Six or eight pin
optoisolators are everywhere and should not be a problem.  4KHz is not high frequency, but a hybrid could use the four tubes on the left displaying the KhZ or MHz value with the other
tubes used as indicators driven by high speed TTL or ECL.
Lastly there are two Japanese edge lit displays.  There are ten etched glass wafers inside; each driven by a 48 Volt miniature bulb.  It is possible to use high intensity LEDs instead of
the bulbs to make it easier to interface to logic chips/drivers but would require one to make a pc board instead of what is there now.  Not a big deal for the determined.
I must say that a blue led display looks really cool.  Any colour LED could be used.  High intensity white and blue are what I have on hand.  The white looks good too.
I suppose mulicoloured LEDs could be used.  An ever changing display with all the colours of the rainbow... Hmmmm....
The two digits I have were used in some sort of time measurement device, probably a clock or time event counter.  The left digit is wired from zero to five while the other is from
zero to nine.  All of the bulbs work but interfacing 48V to CMOS or TTL requires more parts either as discrete transistors or a few high voltage driver chips.  Also, miniature 48V bulbs
are not common any longer.

Dang typo errors... Never see 'em in the preview before posting.  Always after when everybody can see the typos...

[bitseeker]

Welcome back, Enigma-man! That Gen Rad counter looks to be a great condition. Nice power supply upgrade and Nixie mod. For the power cord, it appears that a regular extension cord would work. It's good that the connector isn't recessed like I've seen with some full-width rack-mounted equipment of the era.

Looking forward to seeing your Dekatron-based counter project. RGB LEDs for those edge lit glass displays would be interesting as an additional output channel. As the count goes toward a particular limit, the color could change accordingly, for example.

[Enigma-man]

Yes, a three wire extension cord could work as well.  I used the adapter because it never got used for anything and was lounging around in a box with other cables doing nothing.
Also, the fit from the adapter is very tight and you have to work at it to get it to fit properly.  I didn't want to crack the connector by removing the adapter.  It's easier to unplug the
power cable from the adapter when you have to go inside.

[bitseeker]

Yeah, I remember those adapters for attaching a CRT monitor with a regular plug to a PC power supply. That was a looong time ago. Hmm, I may still have an amber monitor with the correct plug somewhere.

[ben_r_]

Ha! Man there is some cool Nixie tube gear out there! I had no idea there was so much!

[Cubdriver]

Ha! Man there is some cool Nixie tube gear out there! I had no idea there was so much!

Oh yeah, there's plenty of it out there!  Trust me, do NOT look through old HP catalogs.   

-Pat

[VK5RC]

Just a bit of a teaser, like a low cut dress, see enough to raise interest!
My 521C , OK not a real Nixie but of similar vintage/design. A couple of gassy tubes on quick inspection - one rectifier . I will give it it's own post a bit later.

[TheSteve]

The Nixie's in the HP 5340A are the sweetest ones I have come across. I'd like to build a clock using them but can't possibly sacrifice my beautiful working 5340A. Does any other HP gear use same really small nixies? I suspect I'll likely be shopping my favorite auction site for another 5340A to rob the nixies from...

[Cubdriver]

The Nixie's in the HP 5340A are the sweetest ones I have come across. I'd like to build a clock using them but can't possibly sacrifice my beautiful working 5340A. Does any other HP gear use same really small nixies? I suspect I'll likely be shopping my favorite auction site for another 5340A to rob the nixies from...

That there kinda talk might earn ya a beatin' in these here parts...   

 

Off the top of my head I don't know what else uses them, though I'm fairly certain other things do.  I think the 5360A computing counter might use the same ones.  I'm not suggesting that you kill one of those, either, mind you!  I'll try to find the part number of the tube, perhaps you could find some spares on the credit card killing auction site...

-Pat

[Cubdriver]

Rat Shack used to sell a small nixie (think it was a Burroughs part) - RS part number 276-048.  They occasionally show up on the auction site.  That might be something to look for.  Smaller than those in the 5340A, but still nice little display tubes.

What makes my want to cry is that when they were new they were $2.50 each.  Wish I'd bought every one I saw!

-Pat

[TheSteve]

That there kinda talk might earn ya a beatin' in these here parts...   

 

I hear ya! I don't think I'd sacrifice a fully working unit but there are lots out there with some dead parts that are near impossible to replace. And then I'd have a parts unit to help others.

[bitseeker]

The Nixie's in the HP 5340A are the sweetest ones I have come across. I'd like to build a clock using them but can't possibly sacrifice my beautiful working 5340A. Does any other HP gear use same really small nixies?

Yeah, don't sacrifice your 5340. Sell it to me before you do that. Meanwhile, if you haven't already, check out this site for a variety of Nixies. http://www.sphere.bc.ca/test/nixies.html

[edpalmer42]

Just a bit of a teaser, like a low cut dress, see enough to raise interest!
My 521C , OK not a real Nixie but of similar vintage/design. A couple of gassy tubes on quick inspection - one rectifier . I will give it it's own post a bit later.

I had a similar unit.  It was a Beckman/Berkley 7360A EPUT (Event per Unit Time) meter that was spec'ed to go up to 2 MHz.  It worked, but only made it to about 1.5 MHz due to a tube substitution on the LSD (Least Significant Digit).  Four tubes per digit, seven digits.  The digit modules are all socketed.  Remove the screw from the front panel and the digit unplugs.  The LSD unit and maybe the Most Significant were different, but the rest were identical.

I found a recent message thread, with pictures, here:  http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=306292

Unfortunately, it was just too big (19" rackmount, 10.25" high x 16" deep, 65 pounds) and I just didn't have the space for it, so it had to go. 

[worsthorse]

I just picked up a Monsanto 100C nixie tube counter which appears to be working, though I haven't tested it yet. Will post photos later today. Wondering if anyone else has one of these... I am looking for a manual or spec sheet and would like to avoid spending 30 bucks on ebay to get one. thanks - bill

[Cubdriver]

I hear ya! I don't think I'd sacrifice a fully working unit but there are lots out there with some dead parts that are near impossible to replace. And then I'd have a parts unit to help others.

Very true.  There is a custom IC in the signal path that seems inclined to crap out (I have one with that failure).  I ordered what was supposedly a working replacement board about a year ago, but haven't gotten to revisit the counter to install it since then.  The few times that particular IC has appeared on the 'bay, the sellers wanted as much or more for it than I paid for the counter.  My fingers are crossed that the replacement board (when I finally get to it) brings things back to life.

-Pat

[VK5RC]

A new addition - just needed a little cleaning. Works at full speed and sensitivity 12MHz 10mV input

[bitseeker]

Well, well. That certainly looks familiar. Cleaned up nicely!

[VK5RC]

It was the 5216 from Poland, I was outbid on the other recent 5216 - if I recall the other one was from the USA.

[Cubdriver]

Looks nice, Rob!

I finally got mine cleaned up and working, and have been meaning to post a tear down thread but am being lazy.  Perhaps I'll get my butt in gear and do it this week.



More pics at: https://pmanning.smugmug.com/Electronics/HP-5216A-Electronic-Counter

-Pat

[VK5RC]

Hi Pat, I did appreciate the fact you connected yours to the correct era of HP gear , mine unfortunately was connected to some of this modern rubbish - with silly colour displays. In my mind a REAL display is monochrome orange or red or possibly blue/green at a pinch.
Yours looks in great nick, mine is missing the front foot - it has the metal part but not the plastic foot. It is times like this I think about 3D printing - if only there was a linked 3D laser scanner! If someone was able to scan one in - then we could 3D print to our hearts' content. I certainly am not up to that.
The teardown/repair/clean would be interesting+++
Rob

[Cubdriver]

And I replaced the missing tubes in the 522B (cousin to your 521) and tried firing it up the other night.  It works to some extent at least, counting in manual gate mode.  I haven't tried putting an actual signal into it yet as I turned it on on a whim and it's in the living room and not near a signal source.  I still need to do some serious scrubbing to pretty it up, but it shows signs of life despite its age. 

Here's a crappy iPhone photo of it as it came, and at the smugmug link there's a short video of it counting in the timing mode.  The knobs don't seem to be original, but I'm happy that the old beast lights up and seems to function.

As it arrived:


A few other iPhone pics, and the video are here:
https://pmanning.smugmug.com/Electronics/HP-522B-Electronic-Counter

-Pat

[Cubdriver]

The feet are an issue all to often.  Either they broke off down through the years (though they are pretty tough!), or more likely were removed and tossed when instruments were rack mounted.  That or people poach them and sell them separately for stupid $$.  The newer all plastic ones are readily available at barely tolerable cost, but the old black ones usually used on the nixie era gear are not so easily had, and the few I see on the bay are often crazily priced.  It's to the point where I'll bid at least somewhat higher for gear that still has the old black feet.  The one piece type on these smaller instruments are even harder to find.  Ugh!

I must say that it's nice to see that both yours and mine both have their HP emblems intact.  I'd love to stumble upon a box of NOS HP emblems somewhere!  I don't understand why THOSE seem to go missing from so many things.

-Pat

[Johnny10]

I still have 4 cosmetic/mechanical issues with my 5216A.
The plastic screen has a brush mark which needs to be removed. (Some sort of abrasive plastic polish or find another colored plastic sheet ?)
I do not have the proper power plug. ( IEC? File out a new opening?)
The aluminum frame needs to be polished. Tried running a bit of 800 grit sandpaper but still a corroded and dull.
The HZ, KHZ, MHZ screened designators are distorted and missing bits of coating. The lights work fine. (Make stencil and respray?)