[pravous]

With a growing tube collection I decided I needed a way to test and match vacuum tubes. While there are many options out there I decided to order and assemble an Etracer. If you are curious you can check out the website here: Etracer website. The Etracer is a vacuum tube tester that you hook up to a computer which allows you to test just about anything you want to know about a tube. The basic options are a quick scan (results compared to what expected new tube values would be), full scan (complete trace of curves along all voltages), and corner scan (edge case testing at maximum voltages). You have two options when buying an etracer, diy make it yourself from a kit, or have them assemble the kit for you. I chose to assemble the kit myself.
Here is what arrived on my doorstep this past Thursday.

Despite being opened by customs everything was in good order. The basic contents are a bag of hardware (connectors, pins, tube sockets, banana jacks, hookup wire)
a Meanwell power supply, complete chassis and the pcb with the heart of the Etracer (pcb comes already soldered and completed).

Not included with the kit are screws to attach the tube sockets, 5mmx20mm slow blow fuse, a usb A cable to connect the unit to the computer and an optional 80mm fan. I went ahead and ordered all of the above before the kit arrived. I had also read that the provided tube sockets are not the best so I went ahead and ordered some belton and amphenol 9 pin, 8 pin octal, 5 pin ux5 and a 4pin socket since these are the one I will be primarily testing. I also ordered some 4 inch Hammond handles which I saw in another build video.

First up was drilling some holes in the chassis side plates to accept the new handles.

Next up was wiring up the back plate from the IEC power socket over to the power supply.

A couple of notes here. The instructions for this step are quite basic. If you are not familiar with a combo iec inlet, fuse holder, switch assembly you will have to break out the multi meter and use the continuity tester to figure out how to connect the tabs. I opted to use spade connectors and colored solid core wire I had left over from my Bottlehead crack build. I covered the spades with heat shrink as well. The instructions vaguely mention that the USB connector may make a ground connection with the chassis but I opted to make a direct ground connection which you will see connected later. On top of the power inlet is a USB header which is provided with the kit. On the right is the 80mm fan, optional but I decided to go with a noctua. If you do decide to add a fan you will need a 3pin model, the etracer will not work with a 4 pin pwm fan. Once the back panel is all set you can go ahead and start putting the chassis together.

Here is the back view with the back, bottom and side panels all together.

Below is the view from the front showing the power inlet connected to the power supply mounted on the side panel to the right.

You can also see the ground connection (white wire with yellow heat shrink) connected to the motherboard stand off and thus the bottom chassis plate. The usb header connects to the back of the pcb to the right of the ground connection. Make sure to plug in the usb header before screwing in the back plate as the spacing is pretty tight. The red and black wires on the top right connect the iec inlet to the power supply with a molex connector. The connector and pins are provided with the kit. Making these molex connections were the biggest time sink for me. Doable but very time consuming. Last is the fan connection, the instructions let you know that the polarity of the pins on the pcb are reversed from a normal computer fan connection. The solution requires either breaking off the lock tab on the pcb or cutting the fan wires and resoldering. I opted to break off the lock tab and reverse the connector that way.

Now we have power to the power supply and need to get it to the etracer pcb.

Another molex harness is made and along the way you need to adjust a potentiometer on the power supply and dial it into 29V. Once the power supply is hooked up to the pcb the power section is done.

Next step in the front top plate which contains the indicator leds and the banana jacks that will connect to the tube sockets.

Two more molex bundles to make, one for the leds and one from the pcb to the banana jacks.

Test power up and power led and fan are working!

Last thing left is to make the top plate which consists of banana jacks and tube sockets. Very time consuming, I elected to just wire up the 4 tube sockets that I am looking to test.

The kit comes with stranded hook up wire which would not be my first choice. Can be a major pita in terms of fishing it through the tube socket pins. The black shrink tubing locks in the ferrite beads provided with the kit.

Final piece before mounting the top plate is a paper tray which goes below the top plate and catch any metal shaving that might be created by inserting and removing tubes from the sockets.

And after the better part of a day the Etracer is complete!

Probably the most involved diy project I have made to date. In retrospect the $180 fee to have them build it for you seems like a pretty good deal. On the other hand having built it myself I was able to add some tweaks in the handles and better tube sockets. Pretty wiped after building and typing this all up so I will get into the software and actual tube testing tomorrow.

 

[carlman14]

Nice build! I built one of these a while back. I absolutely love it!

 

[pravous]

Sorry for the long delay. I had a component on the Etracer go bad while I was taking screenshots and videos for this post. Luckily Chris Chang, the owner of Essues, stands by his product. Within a day he had diagnosed what component went bad and paid to have the motherboard shipped back to Taiwan, repaired and then shipped back to me.

The software to control the Etracer can be downloaded from Essues website. As far as I am aware the software is only available for Windows. Download and then pick a place to unzip the software. Interestingly it is a local install, you could theoretically install the software on a usb drive and use that to run the Etracer from any Windows PC. The whole folder containing everything required only take @45 megabytes.

Once you have the software installed you have to place a config file that is sent to you from Essues when they ship your kit. This contains the calibrations done to the device before it is shipped to you. Once you do this you can open the software and plug in the Usb cable from the etracer to your computer. Windows then recognizes and installs the usb driver automatically.

Here is what it looks like at this point

Next step is to connect to the Etracer through the software button "Connect" on the bottom left. Here is what it looks like.

At the top right of the screen it shows what version of firmware you are running and on the bottom left it lets you know that you are connected. One last step before you can start testing tubes. On first run with a new software installation you have to do a software calibration to ready the unit. Here is what you get.

Now we can get to the fun stuff testing some tubes! First step is to load the configuration file for the tube you are testing. Essues provides files for @ 122 common tubes with the ability to make your own configuration file assuming you can find a datasheet. Heres what it looks like to load a configuration.

Then select the tube you want in this case 6AS7G

Now you are ready to wire up the tester itself based on the instructions in the software

The circled connections show how to physically wire up the Etracer to test this particular tube. Once wired correctly we are ready to fire up the heater with the "Heater On" button. Once turned on you get information about the voltage and current the heater is drawing.

There is also an alpha version of this software that allows you to configure a heater softstart that fellow Headfier carlman14 told me about. Basically 1/2 voltage for a user configured time period. Now that we have the heater warmed up we can actually do some testing.

There are 3 basic choices, Quick Scan, Full Scan and Corners Test. You can also choose the have all 3 run concurrently with the combo option. I have not played around the H-C Leakage, Basic params or Load Line options yet. Heres the detailed view of Quick Scan, Full Scan, Corners and Combo in that order.

To give you a feel for what it looks like from the software side I recorded this video of a combo (quick, full, corners) on a Svetlana 6AS7G. Feel free to skip 1:45 mark as it is just the countdown settings I use to let a tube warm up.



That about wraps up the basic software overview of the Etracer. The real value in this particular tester in my opinion is the ability to create custom configuration files. My next post will be about making a configuration file using a tube data sheet.

 

[pravous]

While the Etracer comes with configuration files for 122 commonly used tubes there are times when you want to test a type of tube with no configuration file included. This post will be a walk through of how to configure the settings to do a quick scan of the 2c22/7193 tube family. The first step is to track down the tube data sheet for the type you would like to configure. Here is a link to the data sheet for a RCA 2C22.
2C22 data sheet
First step is to open the Etracer software. This is what you see whenever you start up the application.

Next step is to locate the information for your tube type in the data sheet. Here is the data sheet with the information we need highlighted. Heater data in yellow, Class A Amplifier settings for plate voltage in blue, grid -voltage in pink, expected values at these settings circled in green.

The next step is to input these values into the quick scan tab in the Etracer software. I have highlighted the values in the same colors as those on the data sheet above.

Quick scan is now complete so we need to configure the full scan tab. The way I usually go about this is to look at the curve trace graph in the data sheet. The information we need is maximum Plate voltage highlighted in yellow, maximum -grid voltage in green, and range in ma in pink.

We also need to find the maximum Plate Dissipation in Watts found here on the first page in pink.

Now that we have all the data we can input it into the Full Scan tab in the Etracer software. I have highlighted all the fields the same as on the data sheet.

The V step setting controls how many data points will be used to make the curve trace. I usually use the same steps as on the original curve trace for the NEGV steps and the HV1 steps @ whatever value gets me 20 points on each NEGV line. The number you choose for this affects how long the full scan will take, bigger steps result in a quicker scan with a more jagged curve, smaller steps take longer and result in a smoother plotted curve.

The next step is to configure the wiring instructions on the Etracer software. This essentially tells you how to make the physical connections between the Etracer and the socket you are testing with.

Here is where you find the pin outs on the data sheet.

And here is where you create the instructions in the Etracer software.

This tube type is a little more difficult in that two of the connections are made with top caps. I indicated this with the (TC1) and (TC2) notations.
Here is what it looks like configured on the Etracer unit itself.

Now that we have the Quick and Full Scans configured we need to save our configuration so we can use it to actually test some tubes. Two quick steps in the File Tab of the Etracer software.

Now we can load the configuration as shown in the previous post and test a Ken Rad 7193. Here is the quick scan result.

These are the kind of results we like to see when tested a newly bought tube

Here is a full curve trace for a Ken Rad 7193.

Hope this post will be useful to someone who is considering or has recently purchased an Etracer. Not every tube type is this simple to configure. First you have to locate an actual data sheet and then you are hoping that it has expected values, in this case for a Class A amplifier. Unfortunately this is not always the case. It is also possible to find two different data sheets with conflicting values. Here are a couple of spots to find data sheets is you are curious.
Franks
Radiomuseum
Tubebooks
Duncanamps
R-Type
If anyone has other sources I have not mentioned here please post. Always looking for new sources of information.

 

[HiGHFLYiN9]

Very neat piece of kit. It looks like about $1,300 for a turn-key system, the software, plus shipping from Taiwan. That seems pretty reasonable given its sophistication.

 

[barbz127]

How are you finding the kit a couple of weeks on?

 

[pravous]

How are you finding the kit a couple of weeks on?

Still loving it. Feels much better when I acquire a new tube and I can test it before trying it in my amps. Sorry for the slow reply I must have missed the initial notification.

 

[Metric]

That's a great tutorial, I got my Etracer last week and I have been reading the manual from cover to cover to learn how to design new tube config files, this thread really helped!

 

[pravous]

That's a great tutorial, I got my Etracer last week and I have been reading the manual from cover to cover to learn how to design new tube config files, this thread really helped!

Glad this was helpful. Let me know if you want any help with a configuration file.

 

[Metric]

Glad this was helpful. Let me know if you want any help with a configuration file.

Thank you, I would be very grateful if you could look over a tube config file once I make my first attempt and see if I have gotten it right!

 

[pravous]

More than happy to check over your configuration file. Carlman14 here on headfi helped me come up with a configuration file for 5998/421a so if I can’t be of assistance he might be a resource as well. Happy testing, nothing like plugging in a new tube acquisition and being able to see exactly what you have

 

[Metric]

More than happy to check over your configuration file. Carlman14 here on headfi helped me come up with a configuration file for 5998/421a so if I can’t be of assistance he might be a resource as well. Happy testing, nothing like plugging in a new tube acquisition and being able to see exactly what you have

Thanks Pravous, it's certainly a big step going from a Weston 981 Mk 3 to an Etracer, What an amazing machine, I am learning so much more about how vacuum tubes work now that I can see the curves and can vary the parameters. It's also making me study tube data sheets in much more detail. I bought a large collection of tubes from a deceased estate sale in Japan and the fellow was obviously into audio tubes, most of them seem to be new - They are in their original boxes and he folded the original purchase receipts from stores in Tokyo and tucked them in the boxes with the tubes. I am looking forward to testing them... Many of them are not listed in the Etracer config files so I am doing my best to learn how to create new configurations. Currently I am making one for the WE 437A, I am hoping that the tube pins will make sufficient contact with the Etracer's B9D socket.

Could I ask, would you consider sharing your 5998 config with me? I can see that I have a pair of GE (JAN) 5998 tubes here.

I will let you know how I go with the 437 setup once I feel confident enough that I have set up the tester correctly for that type.