atkelar | HP 5512-A Counter @atkelar | Uploaded August 2023 | Updated October 2024, 10 hours ago.
Workshop Project #25 - HP 5512A Counter
One word: NIXIES! I've been hunting for one of these old school counters for quite some time and I got lucky a few weeks ago: This unit was up for grabs for reasonably cheap; it was listed as "untested, as is" and "a good source of nixie tubes for clock projects"... Well, I think I can rescue that beauty from such a cruel fate! Not that I have anything against nixie clocks, but please: don't kill vintage gear for it!
The unit had the fan missing and somebody had put in a crued power cord mod because the built in power socket was not the typical modern ICE one, but rather these oval ones from ye days of yore...
The electrolytics were in pretty bad shape; and this time it's not an estimate but confirmed: I put in reasonable new ones again. Note: I don't have as much selection for the make and model of caps as I'd like: I need a well matching capacity first, a minimum of the same voltage second and thirdly a case that is at least not larger than the original one. Make and Model is last on that list, but if I can find the same ones, I'll gladly take them. In this case though, the tantalum one was so expensive, that I just went for a regular house and garden variety instead. Almost 40$ per piece... with 3+ weeks delivery time... yikes!
0:00 Intro / Overview
1:35 Peek inside / Nixies Are Stuck
3:50 Pulling Modules / Back Panel and Case
5:23 Recapping Start / Gutting Caps
7:29 Stuffing Caps / PCB Recapping and Cleaning
9:33 One More Cap! / Potentiometers And Switches
11:28 Back Panel Re-Mod / Filter Cap Mounting
12:34 Cleanup Time! / Reassembly / Backplane Cleanup / Thermal Paste
14:00 Back Panel Assembly
15:40 Function Switch Cleanup / Front Panel
17:30 Filter Cap Soldering / Voltage Check / -35V Adjustment!
18:38 First Nixie Glow! / Function Check / 100kHz Adjustment
19:45 Real Test / New Fan / New Foam Padding / New Feet
21:20 Circuit Overview
23:30 +/-1 "Error" / Bye / Outtake
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
and also on Patreon: patreon.com/Atkelar
Thanks to everybody who signed up already!
Workshop Project #25 - HP 5512A Counter
One word: NIXIES! I've been hunting for one of these old school counters for quite some time and I got lucky a few weeks ago: This unit was up for grabs for reasonably cheap; it was listed as "untested, as is" and "a good source of nixie tubes for clock projects"... Well, I think I can rescue that beauty from such a cruel fate! Not that I have anything against nixie clocks, but please: don't kill vintage gear for it!
The unit had the fan missing and somebody had put in a crued power cord mod because the built in power socket was not the typical modern ICE one, but rather these oval ones from ye days of yore...
The electrolytics were in pretty bad shape; and this time it's not an estimate but confirmed: I put in reasonable new ones again. Note: I don't have as much selection for the make and model of caps as I'd like: I need a well matching capacity first, a minimum of the same voltage second and thirdly a case that is at least not larger than the original one. Make and Model is last on that list, but if I can find the same ones, I'll gladly take them. In this case though, the tantalum one was so expensive, that I just went for a regular house and garden variety instead. Almost 40$ per piece... with 3+ weeks delivery time... yikes!
0:00 Intro / Overview
1:35 Peek inside / Nixies Are Stuck
3:50 Pulling Modules / Back Panel and Case
5:23 Recapping Start / Gutting Caps
7:29 Stuffing Caps / PCB Recapping and Cleaning
9:33 One More Cap! / Potentiometers And Switches
11:28 Back Panel Re-Mod / Filter Cap Mounting
12:34 Cleanup Time! / Reassembly / Backplane Cleanup / Thermal Paste
14:00 Back Panel Assembly
15:40 Function Switch Cleanup / Front Panel
17:30 Filter Cap Soldering / Voltage Check / -35V Adjustment!
18:38 First Nixie Glow! / Function Check / 100kHz Adjustment
19:45 Real Test / New Fan / New Foam Padding / New Feet
21:20 Circuit Overview
23:30 +/-1 "Error" / Bye / Outtake
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
and also on Patreon: patreon.com/Atkelar
Thanks to everybody who signed up already!
