Vacuum Tube Curve Tracer (The FUtracer)

[KungFuJosh]

This conversation is coming from the "Show Us Your Curve Tracer" Thread, I was asked to start a project thread for it, and here it is...


I had a terrible experience with a popular tube curve tracer. As a result of that experience, I designed better hardware, and hired somebody to create new/much better firmware. The result is what I'm calling the FUtracer (for obvious reasons if you're familiar with the one that pissed me off).



It's setup to test (from left to right):
12AX7 etc...
EF800 etc...
EF86
EL84
EL34/6L6/6V6 etc...

It can be setup for whatever tube types/sockets you want, but those are the ones I cared about, so that's what's on the tube PCB part.

Here's the Windows GUI:


Here's my ridiculous / overkill test I did. 301 points from Va 2 to 400, with 31 sweeps of Vg from 0 to -30:

[KungFuJosh]

For anybody interested, I'm going to order some more PIC chips to program, and then I'll get 5 to 10 kits ready. Initially they won't have anything on the boards, so I suggest anybody interested either has or develops some SMT skills before proceeding with this set. For the future, I'm getting quotes on PCBA service to cover the 5 smaller SMT parts (there's also a couple larger ones setup for easy hand soldering that don't need any special skills).

Thanks,
Josh

[KungFuJosh]

A couple notes about the current PCBs:

The silkscreen:
- There was an error that shows R46 and R48 as 330 ohms, but they're both supposed to be 100 ohms, and won't work with 330 ohms in conjunction with the 4N35 optocouplers.

- BC327 are now EoL (end of life) and can be replaced with BC559 (or BC558).

Parts NOT used:
X1, C29, and C30 are not in use, and there's no point in installing them. I left them on because that may change in the future, but chances are they'll eventually be removed entirely.

The next batch of PCBs will reflect the silkscreen corrections.

I'm also getting PCBA quotes, and will hopefully be able to offer boards with the SMT stuff already done for people who aren't into that kinda thing. 😉

Thanks,
Josh

[Cubdriver]

Tagged for findability, and I've ordered a few SMT practice kits from the jungle place and a used solder paste dispenser from the Bay of Evil.  This should prove to be a useful piece of test gear.

-Pat

[Synthtech]

Great work indeed!

[Johnny10]

 

[KungFuJosh]

Here's some more info on the PCBs, and the GUI. For the GUI, I designed 3 color schemes:

Dark Theme



Darker Theme



Light Theme



Here's the PCBs and programmed PIC chip:


Here they are (mostly) built:



The main PCB, and PSU connection PCB pictured above are both complete, I'm waiting on an order from Mouser for the rest of the SMT parts for the tube socket board. For at least the first 10 sets, I'll include both the SMT and through-hole versions of the socket boards.

I've already tested the new main PCB, and it calibrated perfectly. I'm waiting on finishing the socket board and testing it before I can send anybody any kits.


It's important to note that there is no heater power supply built in to the PCB. This is what I use for the heater power supply: https://www.amazon.com/dp/B01LWXAC5E. I've been using that for a few years, and it works great. I'm sure there are other similar supplies that would also work well.

The PSU connection PCB has two power output connectors, one for the main PCB, and one for the Heater supply.

The main PSU I'm using is this 20V laptop style supply: https://www.amazon.com/dp/B07RDPQ2GW/ - I clipped the end off of that and swapped it with a standard barrel plug, and covered it with some heat shrink for my tester.

Thanks,
Josh

[Cubdriver]

Here's some more info on the PCBs, and the GUI. For the GUI, I designed 3 color schemes:

Dark Theme



Darker Theme



Light Theme



Here's the PCBs and programmed PIC chip:


Here they are (mostly) built:



The main PCB, and PSU connection PCB pictured above are both complete, I'm waiting on an order from Mouser for the rest of the SMT parts for the tube socket board. For at least the first 10 sets, I'll include both the SMT and through-hole versions of the socket boards.

I've already tested the new main PCB, and it calibrated perfectly. I'm waiting on finishing the socket board and testing it before I can send anybody any kits.


It's important to note that there is no heater power supply built in to the PCB. This is what I use for the heater power supply: https://www.amazon.com/dp/B01LWXAC5E. I've been using that for a few years, and it works great. I'm sure there are other similar supplies that would also work well.

The PSU connection PCB has two power output connectors, one for the main PCB, and one for the Heater supply.

The main PSU I'm using is this 20V laptop style supply: https://www.amazon.com/dp/B07RDPQ2GW/ - I clipped the end off of that and swapped it with a standard barrel plug, and covered it with some heat shrink for my tester.

Thanks,
Josh

Looks great!

-Pat

[KungFuJosh]

Looks great!

-Pat

Thank you! For the record, I only designed the themes/graphics, I didn't program the GUI itself. 😉

Thanks,
Josh

[rsjsouza]

Following... 

[coppercone2]

this actually looks useful if someone wants to try to do something advanced with tubes

[Johnny10]

What is different about your design from the other guy's design?

You said you were upset with the; Quality of parts? Design of circuits?
GUI ?

I see you have PCB for the tube connections?

[KungFuJosh]

What is different about your design from the other guy's design?

You said you were upset with the; Quality of parts? Design of circuits?
GUI ?

I see you have PCB for the tube connections?

There are a number of design improvements to the PCB, some circuit changes, component changes, and better quality in general. The result is a faster, and far more reliable product. Yes, also PCBs for tube connections, and external PSU connections. As I mentioned above, there's no heater power supply on the board either, an external PSU is required.

The firmware is also a huge difference, the "other guy's" firmware is trash. Incapable of properly testing a number of tubes. I spent literally years tinkering and chasing down what I thought were parasitic oscillations, but turned out to be flaws in his hardware/firmware. I swapped his board out with mine in my old tester, and instantly those issues were gone with all else being the same.

For example, the GUI I'm using was developed significantly farther for the FUtracer, but the old version of it also worked with the other guy's thing. Attached is an example of trying to trace an EL34 with the other guy's hardware. For contrast, you can scroll up to the 300 point test I did with my hardware/firmware.

Thanks,
Josh

[KungFuJosh]

For anybody interested, I programmed 12 chips, and I'll put together 12 PCB sets to go along with them to start out.

The cost including Priority shipping to the continental US will be $135 for this 3 PCB set including:

• The programmed firmware chip,
• the main PCB,
• 1 tube socket board PCB (Choice of ONE: 1 with mostly SMT, or 1 with only 1 easy SMD chip),
• and a PSU connection PCB.

I will email support docs, the BOM you will need, and a copy of the GUI with my customizations. If you don't specify the tube socket board type, I will send the simpler / less SMT version by default. Or if you prefer both socket boards be included, the bundle price will be $150 instead of $135.

I use Belton Micalex PC mount sockets, which are not on the BOM. Others might also fit. For the octal socket, I removed the mounting ring so it would fit through the top panel with the noval sockets sitting flush for the next one I'm building with this PCB set. I'm using 3/8" standoffs, I'll post photos after it's built.

You'll also want to use a metal enclosure, and make sure the mounting screws with ground/shield connections get continuity to the enclosure (PSU and Socket Board PCBs are earthed via the mounting screws).


As I mentioned previously:
It's important to note that there is no heater power supply built in to the PCB. This is what I use for the heater power supply: https://www.amazon.com/dp/B01LWXAC5E. I've been using that for a few years, and it works great. I'm sure there are other similar supplies that would also work well.

The PSU connection PCB has two power output connectors, one for the main PCB, and one for the Heater supply.

The main PSU I'm using is this 20V laptop style supply: https://www.amazon.com/dp/B07RDPQ2GW/ - I clipped the end off of that and swapped it with a standard barrel plug, and covered it with some heat shrink for my tester. Other 20V laptop power supplies should also work.


If you'd like to order a set, send me a private message and we can figure out payment method and shipping details.

Please keep in mind this is not a beginner project, and both high quality soldering skill and attention to detail are required.

Thanks,
Josh

PS. When stock becomes available, I will place a PCBA order to have an option with the SMT stuff already in place. That version will obviously cost more based on the cost of production.

[KungFuJosh]

I finished building my new version of the board  (the version in the sets), and the tester works great. I used the SMT socket board version, but I'll also be building the through-hole version and applying it to my beta tester unit.

I've already shipped out the first couple orders, and I'll be putting up a website for support, instructions, docs, etc...

Here's an EL84 tube on the new tester:





My daughter insisted on helping me assemble this one:



Here's my two testes:


I'd sell either one of those for the right price. 😉

Thanks,
Josh

PS. Some build photos are attached. But I don't recommend following this layout, I did it backwards from how I intended. It doesn't affect performance, it's just a little awkward to me. I'll post some layout suggestions when I put up the website.

[KungFuJosh]

I swapped out the socket board on the beta unit with the new through-hole version. It works great:



Here's the build process for the socket board:
All the parts needed:



All the parts except the sockets mounted:



I cut off the ring on the octal socket, but you can top mount it if you want and still keep everything flush. I suggest waiting to solder the noval sockets until they're mounted in case the panel holes aren't perfectly straight or something fun like that.


And here's what the two units look like now, we'll call this final:



Thanks,
Josh

[KungFuJosh]

I put the support website up. It's still a work in progress, but the meat and taters are there. Check it out: https://futracer.com

Thanks,
Josh

PS. I wrote it fairly quickly, and didn't do much proofreading, so please let me know if I did something dumb.

[KungFuJosh]

Tagged for findability, and I've ordered a few SMT practice kits from the jungle place and a used solder paste dispenser from the Bay of Evil.  This should prove to be a useful piece of test gear.

-Pat

Have you tried your practice kits yet? How'd it go?

[Johnny10]

Got my PCBs on Thursday

Prepping my soldering area.
Still a while till I get parts together.

[KungFuJosh]

Got my PCBs on Thursday

Prepping my soldering area.
Still a while till I get parts together.

Nice microscope! That should come in handy.

If you manage to gather most of the parts, and you only need a few things, let me know what. I might be able to help, but I don't have much available. Some of that stuff is hard to get right now.

[KungFuJosh]

If anybody is interested, I put one of my testers on Reverb: https://reverb.com/item/47954748-futracer-tube-tester-and-curve-tracer-2021 I put it as $1200 or best offer. Obviously cheaper if you buy direct and I don't have to pay fees.

[KungFuJosh]

If anybody downloaded the GUI zip prior to this week, please download the latest version on the site at futracer.com. There was an issue with the folder structure.

Thanks,
Josh

[ilcaccillo]

Hi, How can someone buy a KIT or contact you?

Your website has no contact info neither an order section

Thanks

[KungFuJosh]

Hi, How can someone buy a KIT or contact you?

Your website has no contact info neither an order section

Thanks

You can shoot an email to support@futracer.com. I'll add contact/purchase info to the website when I have a higher quantity of stock and more people have built their sets. In the meantime I'm trying to avoid getting spammed.

Thanks,
Josh

[KungFuJosh]

For anybody else wondering, the price for the kit (main PCB, Power PCB, socket PCB, and programmed PIC Chip) is $135 within the US, or $135 + actual shipping anywhere else. Contact support@FUtracer.com to inquire.

Thanks,
Josh