Vacuum Tube Curve Tracer (The FUtracer) - Page 1
Forum section: electronics / projects

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 23, 2021, 06:03:52 pm
content: 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...EF86EL84EL34/6L6/6V6 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:

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 23, 2021, 06:05:30 pm
content: 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

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 23, 2021, 06:12:03 pm
content: A couple notes about the current PCBs:The silkscreen:- There was an error that showsR46andR48as 330 ohms, butthey'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

author: Cubdriver
author_rank: Unknown
timestamp: November 23, 2021, 07:11:47 pm
content: 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

author: Synthtech
author_rank: Regular Contributor
timestamp: November 23, 2021, 07:39:10 pm
content: Great work indeed!

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 23, 2021, 07:53:56 pm
content: Here's some more info on the PCBs, and the GUI. For the GUI, I designed 3 color schemes:Dark ThemeDarker ThemeLight ThemeHere'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 thatthere 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

author: Cubdriver
author_rank: Unknown
timestamp: November 23, 2021, 09:49:36 pm
content: Quote from: KungFuJosh on November 23, 2021, 07:53:56 pmLooks great!-Pat

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 23, 2021, 10:12:47 pm
content: Quote from: Cubdriver on November 23, 2021, 09:49:36 pmThank you! For the record, I only designed the themes/graphics, I didn't program the GUI itself. 😉Thanks,Josh

author: rsjsouza
author_rank: Super Contributor
timestamp: November 24, 2021, 12:07:31 am
content: Following...

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2021, 02:49:01 am
content: this actually looks useful if someone wants to try to do something advanced with tubes

author: Johnny10
author_rank: Frequent Contributor
timestamp: November 24, 2021, 03:26:06 am
content: 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?

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 24, 2021, 11:52:19 am
content: Quote from: Johnny10 on November 24, 2021, 03:26:06 amThere 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

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 28, 2021, 03:58:31 pm
content: 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 thatthere 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,JoshPS. 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.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 04, 2021, 02:19:41 am
content: 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,JoshPS. 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.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 04, 2021, 10:44:36 pm
content: 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

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 10, 2021, 09:52:10 pm
content: 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.comThanks,JoshPS. I wrote it fairly quickly, and didn't do much proofreading, so please let me know if I did something dumb.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 11, 2021, 02:05:26 pm
content: Quote from: Cubdriver on November 23, 2021, 07:11:47 pmHave you tried your practice kits yet? How'd it go?

author: Johnny10
author_rank: Frequent Contributor
timestamp: December 11, 2021, 03:15:09 pm
content: Got my PCBs on ThursdayPrepping my soldering area.Still a while till I get parts together.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 11, 2021, 03:55:09 pm
content: Quote from: Johnny10 on December 11, 2021, 03:15:09 pmNice 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.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 15, 2021, 01:03:48 am
content: If anybody is interested, I put one of my testers on Reverb:https://reverb.com/item/47954748-futracer-tube-tester-and-curve-tracer-2021I put it as $1200 or best offer. Obviously cheaper if you buy direct and I don't have to pay fees.

author: KungFuJosh
author_rank: Super Contributor
timestamp: January 20, 2022, 01:36:28 am
content: 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

author: ilcaccillo
author_rank: Contributor
timestamp: February 03, 2022, 11:04:32 pm
content: Hi, How can someone buy a KIT or contact you?Your website has no contact info neither an order sectionThanks

author: KungFuJosh
author_rank: Super Contributor
timestamp: February 03, 2022, 11:39:49 pm
content: Quote from: ilcaccillo on February 03, 2022, 11:04:32 pmYou 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

author: KungFuJosh
author_rank: Super Contributor
timestamp: February 03, 2022, 11:44:51 pm
content: 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

author: KungFuJosh
author_rank: Super Contributor
timestamp: February 05, 2022, 08:52:18 pm
content: I got a laser engraver to play around with.The cover idea looks pretty cool:

author: KungFuJosh
author_rank: Super Contributor
timestamp: February 05, 2022, 10:34:41 pm
content: I retro-engraved the two testers I still have, it came out pretty darn good (though the logo is inconsistent for some reason):Looks cool anyway. I'll maybe try a vector logo instead, or burn it vertically instead of horizontally and see what happens.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: April 11, 2022, 10:57:41 am
content: We're pretty close on releasing new firmware and software versions. Some cool features include a Calibration Wizard for much easier calibration (not that it was that difficult anyway lol), and storing calibration data on the firmware chip.For those that already have an FUtracer, you can send me your chips to update the firmware free, or I can sell a discounted chip instead. That's up to you.I'm also considering making a new socket board version to also including another tube type or two. One I'm thinking about is the 7 pin 6028. Any other desired tubes not yet covered?Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: April 24, 2022, 06:03:56 pm
content: We've been going a little crazy with improvements, and we're testing what's hopefully the final version of the firmware/software for this release.We've added a grid mod that gives much higher accuracy under 200mV. I ran a sweep from 0 to -1 Vg with 10 steps, and this was the results:-002.0mV-100.3mV-199.6mV-298.2mV-396.5mV-495.1mV-593.5mV-692.1mV-803.0mV-901.7mV-1.002mVThat's pretty darn good.I made a video clip showing tracing live in full screen with the latest version of the FUtracer software:https://youtu.be/dle7xnOKeK4Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: May 07, 2022, 12:47:50 am
content: I think we're finally almost done with the new firmware/software versions. Tracing is twice as fast now! Check it out:Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: May 24, 2022, 09:55:50 pm
content: The new versions are finally done. We've added some cool features/and general improvements. The latest version of the GUI is live on the futracer.com website.New kits will ship with the latest firmware (currently version 2.07). For anybody that already has a kit, you can send in your chip to be upgraded for free, or you can purchase a new programmed chip for $30 including shipping within the US.Email support at futracer.com to inquire.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 21, 2022, 09:25:10 pm
content: Here's an update for anybody interested:There's a mod for the version 6.9 PCBs on the futracer.com site for better low grid voltage accuracy between 0 and -1V.I've recently ordered v7.0 PCBs that include the higher grid voltage accuracy. This set is 2mm thick, ENIG surface finish, 2u” gold thickness, 2oz outer copper weight, and include the USB chip and socket, PGAs, and anti-static SMT stuff already done.Once I receive them, I will build 1 or 2 units to test them out, and then I'll have some PCB kits available for sale (price TBD), along with an updated build instruction set for this version.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 07, 2022, 05:41:31 pm
content: I got the new FUtracer v7 boards in, with the PCBA service done...and they're awesome! They did a great job with those tiny little bastard SMT chips.I built it, calibrated it, and tested it, and it's all good. I'm waiting on a couple tube sockets then I can test the new socket board version that also includes 408A (7pin) and similar tubes.Once that's all tested, I'll put together some kits for anybody interested.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 15, 2022, 12:30:01 am
content: My missing sockets are on the way, but I felt like doing a test anyway. Looks pretty darn good for an old 6P14P tested without an enclosure.The test setup (powered by a bench PSU):A quick set of curve traces:Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 22, 2022, 04:01:54 pm
content: The new version 7.0 FUtracer kits are fully tested and ready to go.This set is 2mm thick, ENIG surface finish, 2u” gold thickness, 2oz outer copper weight, and include the USB chip and socket, PGAs, and anti-static SMT stuff already done. The price for the new kit with the Main PCB, Socket Board PCB, PSU connector PCB, and programmed/user updateable Firmware Chip will be $200. Shipping outside the US is extra, but within the US is included for now.The new socket board version is mostly SMT. If you want a kit with the SMT work on the socket board done, I will supply the parts and do the SMT work for an extra $50. The pads are all hand-soldering sized, so don't be too scared if you want to do it yourself.This is the set:You can contact 'support at futracer dot com' for more info or to purchase a kit.More information including build and use guides is available at futracer.com.Here was the final test setup:Thanks,Josh

author: b_force
author_rank: Super Contributor
timestamp: October 22, 2022, 04:32:50 pm
content: I am also popping in just to stay updated!Funny enough I had a similar idea, probably for VERY similar reasons to develop my own tracer.I am actually very curious what you did for the HV boost converter, because that one most definitely needs attention from "the other guy".Otherwise just send me a PM, because I can share a design I am working on (for another project)..Personally I would do things differently, just to try to cut down in cost (not quality), but that is also a matter of taste and preferences.The reason the project went on the (Far) back burner for me, is that personally the SPICE models that can be found seem to be adequate enough to design circuits around them.One little thing of feedback, the engraved numbers on the chassis now say "ECC83, EF800, EF86, EL83, EL34", but that seems to be rather confusing?Assuming that it's possible to also be able to trace other tubes as well.So I personally would stick to a more generic name instead.Also, I assume that the last picture above my post is a prototype?Because the wiring can need some attention.What's the reason to go for ENIG finish as well as extra thick copper btw?

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 22, 2022, 05:28:30 pm
content: Quote from: b_force on October 22, 2022, 04:32:50 pmlol, I'm not surprised. Let's just say we're not the only ones. At least for now, this is the final version of the project. In the future I may wish to do a higher voltage / current version, but it's not a priority for my tube uses. I test partly for design, but more often for quality and targeted values for a given circuit.Quote from: b_force on October 22, 2022, 04:32:50 pmThat chassis was marked for me, but you're correct, any common pinouts will work with their respective sockets. I used those tubes rather than listing all the common tubes that work, since most are pretty straight forward. If you have a simple naming scheme that isn't confusing, I'm all ears. I actually do have a custom chassis being made for the new set, so I'd love to get some ideas on better labeling. I didn't want to do 12AX?, that looks weird to me.Quote from: b_force on October 22, 2022, 04:32:50 pmThe picture above your post was my setup for testing the boards. It's not a prototype, but it's not the intended setup either. It should be properly setup in an enclosure.Quote from: b_force on October 22, 2022, 04:32:50 pmBetter quality, and the best options / for ROHS compliance.Thanks,Josh

author: b_force
author_rank: Super Contributor
timestamp: October 22, 2022, 06:54:14 pm
content: Quote from: KungFuJosh on October 22, 2022, 05:28:30 pmI don't follow the "best option for ROHS compliance" ?The finish is either ROHS compliant or not.

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 22, 2022, 07:11:53 pm
content: Quote from: b_force on October 22, 2022, 06:54:14 pmI missed a slash. Best option / for ROHS compliance. I guess also because I like overkill.Thanks,Josh

author: b_force
author_rank: Super Contributor
timestamp: October 22, 2022, 07:14:46 pm
content: Quote from: KungFuJosh on October 22, 2022, 07:11:53 pmHa! no worries, yeah that makes more sense.Nothing wrong with overkill

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 22, 2022, 07:19:28 pm
content: Quote from: b_force on October 22, 2022, 07:14:46 pmlol, yeah, making sense is good though.I love overkill when it comes to quality. I'd rather pay a little more than worry about trace quality or anything like that.EDIT: okay, okay, also because ENIG looks prettier.

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 19, 2022, 11:21:56 pm
content: If anybody is interested in a kit, but holding off because of part availability, let me know what you need. I've got some of the harder to get stuff including KSA1156YS, KSP94, KSP44, LM377T, etc.I ship USPS Priority- so far it's been $10 within the US, $50 to Australia.The v7 kit is $200 USD. I can supply and install the SMT stuff on the socket board for an extra $50.You can see more info including BOMs for the rest of the parts at futracer.comThanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 22, 2022, 02:43:51 pm
content: Does anybody have a better idea for a socket labeling scheme?I'm finally having a proper custom enclosure made, and I will need to label it.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 25, 2022, 12:10:10 am
content: Any opinions on this for a socket scheme?Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 27, 2022, 02:31:04 am
content: I removed 6V6 and added KT88 to the S6 info. I figured that might be a more useful distinction for anybody that doesn't automatically know KT88, KT66, KT120 would work in that socket.

author: byoungblood
author_rank: Contributor
timestamp: November 29, 2022, 03:23:09 pm
content: Quote from: KungFuJosh on November 22, 2022, 02:43:51 pmI would suggest using the standard EIA basing ID along with a couple of tube type examples. For instance, the octal socket on your tracer uses the 7AC basing, 12AX7, etc, uses 9A, etc..All of my RCA tube manuals have that information with every listing, it would make quick work of looking up TV pentodes that have similar pinouts to EL84s, 6L6s, etc., for the mad scientists out there that want to try to make use out of cheap tubes.May I also suggest adding a breakout for a top grid/plate cap wire? Also maybe a 2nd octal socket for testing octal dual triodes? Or, maybe use some DPDT relays to toggle the pin configuration of a socket to account for tubes that are near identical to one another save a swapped pin? Thinking about tubes like the 6U8/6AN8/7199. It may add unwanted complexity to the design, but just throwing the idea out there.What is the process of adding other tubes to the software?I'm very tempted with the price/features. May sell off one of my tube testers and pick this up!

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 29, 2022, 04:35:46 pm
content: Quote from: byoungblood on November 29, 2022, 03:23:09 pmThat's a great idea with the EIA basing, thanks! I already found them for those 6 sockets and will change my scheme to include them.You can certainly make a breakout to mod the sockets if you need to. The tube socket PCB is setup to use PC pin sockets, but if you build your tester with solder tab sockets instead, you could easily implement switching if you want. Just be careful not to make the leads too long, as you don't want to introduce parasitics.You can add additional sockets if needed, or even skip the socket board if you want, and create your own tube socket scheme. Only word of warning is that the socket board makes it super easy to get good results, and wiring your own socket array requires very careful planning. Needs to be looped, ferrite beads every other socket, etc.Adding tubes to the software is really easy, and the software already covers a lot of tubes not covered by my socket board. Here's a link tomy tube data filethat goes with the GUI so you can see what's already there. You can add tubes either in the data.csv file or through the GUI. In the GUI, you can set the test parameters, adjust the pinout, and then click "change" and it will ask you what name to save the tube:Keep in mind my kit only includes the PCBs and firmware chip, though I am including a few hard-to-get components right now. For the rest of the parts you need, look at the futracer.com site for the BOMs.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: November 29, 2022, 04:51:54 pm
content: Here's the updated list, but I likely won't have room to include everything here:S1:9A: 12AX7, AT7, AY7, 6072, 7025, CV4004, M8137, 6057, B759.S2:7BD: 6028, 408A, 6AU6.S3:9AQ: 6BX6, 6BY7, 6F19, 6GK7, 7ED7, 8D6, EF800, EF811, PF818, W719, Z152, Z179, Z329, Z719, Z749.S4:9CQ: EF86, 6J32P, 6267.S5:9CV: N709, 6BQ5, EL84, 6P15, 6P14P, 7189, E84L, CV2975.S6:7AC: 6L6, 5881, EL34, 6V6, 6550, 6CA7, 7581, KT88, KT90, KT100, KT120 and all others with 7AC, 7S, or 8ET base pinout.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 03, 2022, 05:43:34 pm
content: I made this as a full-size test on some scrap wood:I might make the legend text slightly larger, but I think it looks pretty cool.Dimensions are 9 inches tall, by 7.5 inches wide. I have a second version for custom panels to go with a longer Hammond box (8x12). Not sure if I'll make those or not though.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 06, 2022, 03:51:06 pm
content: I made the legend text bigger, and added more to the 9CQ socket info.

author: KungFuJosh
author_rank: Super Contributor
timestamp: December 15, 2022, 03:53:23 pm
content: I think it came out pretty awesome.

author: mawyatt
author_rank: Super Contributor
timestamp: December 15, 2022, 06:01:09 pm
content: Agree, very nice indeedBest,

author: snapper
author_rank: Contributor
timestamp: April 25, 2023, 04:42:34 am
content: Idea, software, firmware and hardware mostly stolen from roland dekker's project µ-Tracer 3and then badmouthing the developer, i just find people like that to ......https://www.eevblog.com/forum/projects/project-vacuum-tube-curve-tracer-(the-futracer)/msg3833570/#msg3833570

author: KungFuJosh
author_rank: Super Contributor
timestamp: April 25, 2023, 01:47:49 pm
content: Quote from: snapper on April 25, 2023, 04:42:34 amSimply not true. I paid to have better firmware programmed from scratch (and helped with the development of it). I designed better hardware. The software is also 3rd party, and has nothing to do with Roland.This all happened, as I've explained, because my experience with Roland's setup was terrible, and his attitude was worse. I don't care if you like me or not, but don't make stuff up.Oh yeah, nothing about this "idea" is original. That schmuck didn't invent tube tracing. 🙄If you don't have anything to add to the conversation, then don't join in!

author: KungFuJosh
author_rank: Super Contributor
timestamp: May 10, 2023, 01:29:40 am
content: I liked the laser version, but I decided to try out their silkscreen service. I gotta say, I like it.

author: electrolust
author_rank: Unknown
timestamp: May 10, 2023, 05:38:28 pm
content: Just a tourist, but 2 ideas come to mind.1. pluggable tube adapters in a single universal port, rather than individual, fixed/specific ports.2. binning/matching function in the software.refhttp://www.hagtech.com/pdf/vacutrace.pdf

author: KungFuJosh
author_rank: Super Contributor
timestamp: May 10, 2023, 05:43:24 pm
content: Quote from: electrolust on May 10, 2023, 05:38:28 pmIt's not a bad idea, but Nick (who made the firmware & GUI) had a similar idea. He designed a relay board with 7, 8, and 9 pin sockets (one of each), and the board is entirely controlled by the GUI.It's a functional idea, but increases the cost (and size) and isn't for everybody...yet. I may go that route in the future, but for now, this covers everything I need to trace (and more).Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 29, 2023, 09:37:27 pm
content: Okay, so pluggable adapters is necessary sometimes. I recently needed to test some subminiature tubes for a tube mic that needed a tube with more headroom.I found a subminiature to octal tube adapter, then I used my laser to mark the holes to match my EL34 socket. It worked out great:(none of the pins are actually touching each other, it's an optical illusion)

author: mawyatt
author_rank: Super Contributor
timestamp: September 30, 2023, 02:32:11 am
content: Nice!!Best,

author: djsb
author_rank: Super Contributor
timestamp: August 01, 2025, 03:20:52 pm
content: Are your kits still available? Will they continue to be in the future? Thanks.

author: KungFuJosh
author_rank: Super Contributor
timestamp: August 01, 2025, 03:36:25 pm
content: Quote from: djsb on August 01, 2025, 03:20:52 pmI'm out of stock right now, and there's a waiting list, but I will be restocking soon. I also make fully built/calibrated FUtracers, but there's a waiting list for those too.The tariff situation is making everything more annoying than normal. I expect to be restocked to some degree within a month or two.Thanks,Josh

author: Avinunca
author_rank: Newbie
timestamp: September 30, 2025, 04:33:15 pm
content: I would suggest potential customers visit the site of the original creator Ronald Dekker. I'm going to order his uTracer6. He seems a genuinely nice helpful guy. What I've read on here leaves a bad taste in my mouth - especially the bad-mouthing.https://www.dos4ever.com/uTracer3/uTracer3_pag0.html

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 30, 2025, 04:53:44 pm
content: Quote from: Avinunca on September 30, 2025, 04:33:15 pmIt's not bad-mouthing if it's an accounting of actual experience, which it is. It's the truth. You don't have to like the truth, but it is the truth.In any case, it's in poor taste to come in this thread and post links to a different project. That's like going into a Siglent thread and saying you don't like it, so go check out this Rigol. Now that's in poor taste!Anyway, I hope your experience is better than mine. Good luck!

author: watchmaker
author_rank: Unknown
timestamp: October 01, 2025, 10:27:05 am
content: This is very cool. Not to detract, but did you see my Hickok Transistor Curve tracer w/ which Hickok gave instructions for using as triode tracer? Kind of a retort to those who think you poached someone else's idea.BTW, the manual (VHTF and I forget where I got it) has some very interesting applications that may give you some ideas.Regards,Dewey

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 02:17:16 pm
content: Quote from: watchmaker on October 01, 2025, 10:27:05 amI did! Those are cool. I usually enjoy seeing old tube testers and curve tracers whether for tubes or transistors. It sometimes makes me want to make something to work with a modern scope.Thanks,Josh

author: Avinunca
author_rank: Newbie
timestamp: October 01, 2025, 05:21:13 pm
content: You said ....post links to a different project? I will refrain from the obvious comment. If as you say Ronald's design was so badly flawed, did you discuss the issues with him? Did you get a poor response or perhaps an unfriendly reply?

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 05:35:09 pm
content: Quote from: Avinunca on October 01, 2025, 05:21:13 pmAll that information was already stated.Your opiniononmy personal experienceis irrelevant and unsolicited.

author: UnijunctionTransistor
author_rank: Frequent Contributor
timestamp: October 01, 2025, 09:07:41 pm
content: Nice, really nice.Please educate me: were the Nuvistors ever used on audio equipment?I remember seeing a couple in an old Sansui integrated receiver, but perhaps they were used on the RF stages.

author: TimFox
author_rank: Super Contributor
timestamp: October 01, 2025, 09:48:35 pm
content: Quote from: UnijunctionTransistor on October 01, 2025, 09:07:41 pmYes, Nuvistors have been used in audio equipment.Ampex had a classic professional tape deck that was all-Nuvistor:https://www.thehistoryofrecording.com/Manuals/AMPEX/mr-70_manual.pdfSince during the heyday of tube hi-fi equipment, 12AX7s were much cheaper than Nuvistors, they were uncommon in the audio chain, but often used in the RF stages of FM tuners because of their superiority to 6BQ7s.I have built Nuvistor preamps for my own use, using 7586 triodes, since they are reasonably linear and operate nicely at lower voltages (75 V on the plate).They have a reputation for microphonics, but I haven't seen the problem (I shock-mounted the circuit boards due to that reputation).They are still available from NOS dealers, but is harder to find the sockets.

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 10:04:30 pm
content: Some were supposedly used (with circuit mods) to replace VF14M tubes in U47 tube mics. That's interesting to me, as I've built variations of the U47 with an EF800 and a different version with 408A tubes. I dunno if I'd try making a mic with a Nuvistor without hearing one first though.

author: TimFox
author_rank: Super Contributor
timestamp: October 01, 2025, 10:35:40 pm
content: Yes, Nuvistors were used in Neumann microphones after the supply of VF14s ran out, but purists don't like them.I'm not sure of the details: perhaps the circuit parameters were not properly changed for the different tube characteristics, or perhaps there was a microphonic issue.

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 10:51:18 pm
content: I assumed all of that would be the case.I'm very happy with the EF800 and 408A variants, so I'm more likely to stick with those. Especially since I already have tubes for them.

author: David Aurora
author_rank: Frequent Contributor
timestamp: October 02, 2025, 02:45:18 am
content: Quote from: snapper on April 25, 2023, 04:42:34 amI've got no dog in this fight as I don't own either (I nearly bought a uTracer at one point but ended up getting a 576 and rolling my own digitising setup), but that's a pretty bold claim.First up, curve tracers are not a recent invention, and they certainly weren't invented by Roland. And second, there are only so many ways to design one. If there's unique, innovative circuitry Roland has designed that bears no resemblance to other curve tracers and KungFuJosh has blatantly copied it then I'd love to see side by side schematics to prove your point (at which point I'd probably pile on and trash him too). But if the similarity is that it has sweepable supplies, a step generator, some ADCs to read the measurements and some software to control it/plot the output... yeah, nah.

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 02, 2025, 03:16:01 am
content: Quote from: David Aurora on October 02, 2025, 02:45:18 amMy motivation for creating this was simple: the existing option fell short in both quality and customer support, a conclusion I reached through frustrating first-hand experience.In my opinion, the FUtracer is an improved version of a public-domain design, featuring key hardware improvements, better firmware and software, and higher-quality PCBs. It has proven to be a welcome upgrade for a growing number of users. Frankly, any negativity I've encountered has exclusively come from those without first-hand experience, which is why the positive feedback from those who have put it to the test carries far more weight.Thanks,Josh

author: UnijunctionTransistor
author_rank: Frequent Contributor
timestamp: October 02, 2025, 04:41:34 pm
content: Quote from: TimFox on October 01, 2025, 09:48:35 pmThanks for sharing. During the early 1980s, I serviced professional audio equipment, and Ampex tape recorders were found on all recording studios. Although at the time, they were all already transistorized.