GALVA (https://www.f5bu.fr/galva-about/) is a wonderful drawing program written by Jean-Paul F5BU that’s ideal for creating meter faces and front panel layouts. Jean-Paul has installation instructions written in English (A_Lire-Read_Me.pdf) and a tutorial written in English (Galva_Tutorial.pdf) that describe Galva. You can find these documents in the Galva directory after you have downloaded and unzipped the installation file.
The Galva script commands are in French, but there’s only about 10 commands that you will need, so it’s easy to learn.
Below is an example of a meter face that I made for a AC/DC voltmeter project using Galva.
With Galva meter faces are “drawn” using a procedural scripting language, a little bit like BASIC but without line numbers. GOTOs and IF statements can serve as a good way to skip a block of code, for testing or to have “options” withing the code. An apostrophe causes all following text on that line to be a comment. Script commands that end with an underscore are logically continued on the next line.
Left Click on any script command (so that your cursor is inserted somewhere on that line), press F2, and it will open a small window where it will tell you about the command in the language you have chosen during program configuration – likely English if you are in North America or UK. If the command uses parameters, you can view and edit those parameters as well in this small window. Jean-Paul call this small form window a Mask. Click the “Valider-OK” button on the form when you want to save that data and the results will appear in your script listing on the right side of the screen. Press F4 to “run” the script and see the result of your changes on the left side of the screen.
Note that meter representation you see on the computer screen is just a low-res rough-draft. Rest assured that what will be printed on your printer will be high-res and will look terrific.
Installing Galva
Installing Galva is straight forward. Unzip the download file and run the SETUP program. However, I have two suggestions that I encourage you to follow. First, the SETUP program will very likely suggest that you install the Galva program files to C:/Program Files(86)/Galva. Instead of installing it there, where the directory is write protected by the OS, I would recommend that you install it to C:/Galva. This will make your life easier when updating the Galva software (in particular when updating via Galva_MAJ_322.ZIP). Next, during the SW install process, Galva will likely suggest that your data files should be stored in “C: /Users/username/AppData/Roaming/Galva”. Instead, you can store your Galva scripts (the programs you write in Galva) in any directory you like, including where the Galva program itself is stored (if you are not saving to “Program Files(86)”). For me, I chose to put my script files in “x:/user/name/Documents/Galva”, where “x” is the name of the drive where my Documents folder is stored, and “name” is my user name on that particular computer.
Making a New Meter Face Layout
When I start a new meter face the first thing I do is remove the existing physical meter face from the meter and scan it on a flatbed scanner at 300 dots per inch (dpi) as a JPG image. I’ll later include this scanned meter face JPG in my Galva script to use as a temporary background for alignment of the new meter face. To facilitate that background view, because the Galva script command to include an image as a background does not include a transparency setting, I will use an image editor to make several versions of my meter face scan JPG at different transparencies (usually 50%, 60% and 70%) and include that transparency value in the saved JPG file name (scaleABC-50, scaleABC-60, scaleABC-70). That way when I want my background meter scan to have more “fade” and can just change the suffix of the image file name in my Galva script.
Next I find one of Jean-Paul’s example meter faces (there are lots of them to choose from) that is close in style to what I want. Please note that in your Galva DATA folder you will find a zip file titled “Galva_dat_en.zip”. The is a zip archive of meter examples with English comments. I found that I needed a late-version of 7-Zip to extract the files without error. When I initially used a very old zip extractor I got only a partial extraction followed by a CRC error. So if you have any problems extracting this file be sure to use a recent version of 7-Zip or something similar. Keep in mind that the actual script commands are in French and you can’t change that to English. But that’s hardly a problem. The English comments in the script file are very helpful. Make yourself a crib sheet for the commands. Learn something new!
I then comment out (or use GOTOs or IF statements) to make most of the program blocks ineffective. And then un-comment several lines at a time, to learn what those lines do, and how to change them to match my new meter face. After doing this for ten to twenty minutes on your first new meter face you’ll start to get the hang of writing scrips for Galva.
One of the things I really like about Galva is that the user can define the meter face pickets (the little tick lines that are perpendicular to the arc scale) in several different ways. They can be (1) linearly spaced at regular intervals, or (2) follow some mathematical formula, or (3) defined by a table of values. That table of values option is great when you are making a meter face for a meter that is driven by some non-linear circuit that doesn’t follow some nice mathematical formula, or to correct for errors particular to that specific piece of equipment (Hewlett Packard was doing this in the early 1960s, amazing! https://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1961-03.pdf ).
Zoom and Pan
To Zoom in on the Meter Display area on the left side of the screen click Zoom on the top side menu bar or press F7. To change the Zoom factor put a number from 1 to 7 in the zoom box and press Enter. I’m usually at Zoom factor 2 for most of my work, but sometimes I also use higher values. To quickly return to your startup Zoom factor (or 1 if no startup factor) press and hold CTRL then click Zoom or press CTRL+F7. To pan your graphic on the left side of the screen double-click on the position you want to be the center of your display. There’s also provisions for a correction factor to read dimensions off your computer monitor – see the GALVA help file for more information on that.
My Sample Files
Below is a link to a folder with some of Galva scripts that I use for my meter faces.
https://ad7i.net/galva-samples
These scrips are just modest changes to the example scripts that Jean-Paul developed and included with Galva. The Galva script file names begin with the intended meter size, then function and scales. Files with .DAT extensions are Galva script files. Files with .JPG extensions are flatbed scans of original meter faces that came with the original meters. Files with .PDF extensions are meter faces ready for printing, usually onto 4×6″ paper.
Printing Meter Scales
When I first started printing Galva scales I was pleased they looked so great on my monochrome laser printer but dismayed at how poorly they looked on my inkjet printer. It turns out that using the settings for “Photo Paper” and “High Quality” on my Canon G4070 series ink jet printer was the problem. Regardless of what paper I use with my Canon ink jet (photo glossy, photo luster, photo matte, premium copy paper or the cheapest paper available from the big box store) I always get the best printing results for Galva meter scales when I set the inkjet printer driver to “plain paper” and “standard printing”. Go figure.
Printing in a way that gives you the exact dimensions of your design, without wasting a lot of paper can be a bit of a challenge. I’ve outlined below the process that I use, in case it’s helpful to you. It’s a two part process. Part 1 is to make a PDF of the meter face in horizontal (landscape) orientation. Part 2 is to open the PDF, rotate it to a vertical (portrait) orientation and print the PDF onto paper.
To make the PDF, from Galva I selected File->ChoosePrinter and then choose CutePDF Writer (which must have been previously installed – it’s free). Then select More Settings followed by Advanced and then click on the plus sign in front of option for Paper/Output and then use the pulldown menu to select Postscript Custom Page Size and then Edit Custom Page Size, choosing width 6 inches and height 4 inches. You are telling CutePDF to orient the print as landscape orientation. Then click OK on all the boxes to go back up the selection tree, ending with clicking Print (even though you are just choosing the printer and not yet actually printing). With that in place CutePDF is selected and configured.
While still in Galva I next select File->Print to create the PDF file. I will be prompted with a proposed file name and location to store the file. If I don’t care for the proposed name and/or location I change those values to something that suits me better. I then click on Save, which will save the printed file as a PDF.
With the PDF file now created, it’s time to print the PDF. I open the PDF file using a PDF reader – I use Adobe Acrobat Reader. I then rotate the image left by 90 degrees (View->Rotate View->counter-clockwise), so that the PDF image is in portrait orientation. Next, put I put a piece of paper in my printer. Typically that’s 4×6 inch piece of either Red River UltraPro Gloss or Inkpress Media Luster paper, but most any photo paper will work well. Then from Acrobat Reader I select Print, and the Acrobat Print Window opens. I then select my printer (for me it’s a Canon G4070 series ink jet) and then I select Properties for that printer and ensure that I’m using basic settings of Plain Paper (yes, Plain Paper even though the paper is actually photo paper), Standard Quality and Auto Color/Intensity. I then select a Page Size of 4×6 inches, make sure I’m in portrait orientation and click OK. That takes me back to the Acrobat printer page. Under Paper Sizing and Handling, I click on Size and then I select the radio button for Actual Size. This will ensure that I print at the correct scaling factor (100%). I then click Print and about half a minute later the meter face print pops out of the printer. I check the size of the meter face print with a measuring scale to ensure the face graphic is the correct size on the paper.
Once I have the meter face printed onto paper I glue the backside of the meter print to the backside of another (blank) sheet of the same paper using an Elmer’s glue stick. That way I get a double thickness result and if there is a bend to the paper as it sat in the box for months (or years) the two pieces of paper, glued back to back, will tend to offset the bend. Next, I use a fresh #11 X-Acto® knife blade* and a metal straight edge to carefully cut the paper meter face to the lined dimensions. I put a piece of foam core board under the paper meter face when cutting with the knife, so that the knife blade passes through the paper meter face but the blade does not dull as quickly as it might with something more dense was under the paper. When I make a cut, the first draw of the knife is to simply score the paper. I then make additional knife draws to actually cut through the paper. For some of the shorter cut segments I don’t even bother to use the straight edge and instead make the knife draw freehand. Cutting short lengths freehand turned out to be easier than I expected. For the cutout around the meter movement itself, I don’t even try to cut a circle, because I never get it quite right. Instead my meter prints use three or four straight lines for the cutout around the movement. To cut out the holes for the mounting screws on the meter face I’ve tried drilling the holes with a drill press (too much tearing of the paper) as well as using a 3mm hollow-point punch intended for leather cutting (dents the paper too much). What I’m now doing for the screw holes is to edit the Galva script to cause a square to be printed inside the round screw hole graphic, and then again use the X-Acto® knife blade to cut out that square for the mounting screws to pass through. Using knife-cut square holes for the mounting screws is working pretty well for me, and I don’t end up with a distressed paper scale like I did with drilling or punching.
Meter Sources
Like most hams who are builders, I have a small box of old Weston, Triplett, and Simpson panel meters. But I can’t make myself disassemble those classic meters and insert new meter faces. I think that will have to wait until I’ve turned to dust and then the next owner of those classic meters can take on that task.
Instead, I use cheap meter movements from Ebay and AliExpress. When I want a larger display I use a 100x80mm meter and for midsize I use the 64x56mm meters. I usually buy based on price and seller’s ratings, and I don’t worry too much about the meter’s “as sold” functionality, because I will usually drive them with an op-amp and a series resistor – I can change the series resistor value to suit the meter. Most (but not all) analog meter movements themselves are natively current meters in the range of 50 uA to 5 mA. If the meter is sold as a voltmeter there’s usually an internal series resistor to convert the small current response to one that’s a larger voltage response. If it’s sold as an ammeter there’s usually an internal shunt resistor, although I’ve seen some pretty weird amp meter shunts inside cheap meters. In general, I’ve found it’s best to buy meters that are sold with native full-scale values of 50 uA to 1000 uA DC. My primary preferred meter for general use is a 500 uA meter. The 500 uA meter seems to require the lowest voltage needed to achieve full scale deflection (see 64x56mm table below), compared with 50uA, 100 uA, 200 uA and 1 mA meters.
But if you have some other type of meter, you can usually return it to “native small current meter mode”. AC meters usually have some sort of a diode bridge internal to the meter (along with a series or shunt resistor). To restore the meter back to its “native current mode” I open up the meter and remove any diode bridge, short any series resistor and cut out any shunt resistor, and then reassemble it. I then connect the meter movement to a series circuit consisting of the meter terminals (now directly connected to the meter’s coil), a 100K ohm fixed resistor, an accurate digital multimeter in current mode and a 0-20 volt variable power supply. I then adjust the power supply voltage for a full scale deflection on the analog meter. If I can’t get full deflection I reduce the resistor value by a factor of 10 and try again. Once I have the meter at full scale deflection I read and record the current value displayed on the digital ammeter multimeter. I then remove the digital multimeter from the series circuit and, if necessary, readjust the power supply for full scale deflection. I reconfigure the digital multimeter for measuring voltage and then measure and record the voltage across the meter terminals when the meter is at full deflection. I then use ohms law to calculate the resistance of the meter coil (voltage / current). For most meters in the range of 50 uA to 5 mA I usually get about 50 to 250 mV across the meter terminals. For a 50 uA meter the resistance is usually 2500 to 5000 ohms. For a 1 mA meter the resistance might be 100 ohms.
I’ve had few problems with the meters I’ve received via Ebay and Aliexpress. When I have had a problem with a meter (sticky or jumpy movement) it’s always been (so far) that somehow the movement spring got hung up on the some element of the movement. Maybe it was dropped during transit, who knows. To correct the problem I carefully manipulate the spring with a wooden or plastic toothpick to release it and that has always (so far) solved that problem without adverse effects.
In late 2022 and early 2023 I purchased meters in the $4.50 to $6.50 range (includes shipping) on Ebay from seller Huapingshu, yibiaoxin1982 and on AliExpress.com from JU QI Quality Store, TAIYEDQ Global Store and Zhongong Store. The meters in the best cosmetic condition (pristine clear meter cover) were from JU QI Quality Store, but I suspect that all these sellers are simply reselling stock they get from a common distributor or liquidator, so what I got with one purchase from a particular retailer may be different than what I get from the next purchase from the same retailer. I’ve also seen strange issues with shipping charges. Order only one meter from a vendor and the shipping is free. Order two meters (exact same meters) from the same vendor and the shipping charge jumps from free to $9. Keep a watchful eye out for those types of things.
Here are some typical electrical characteristics for these inexpensive meters which were received in native mode (no shunt resistor, no series resistor)
64 x 56 mm Meters, Full Scale Values
Full Full
Scale Scale
uA mV Ohms
46.2 207 4480
49.0 250 5100
100 176 1850
104 158 1520
488 74.2 152
500 77.3 155
490 75.7 154
1004 208 207
From the data above one can see that, for the 64 x 56 mm meters, from a voltage perspective, the meter that reaches full scale with the least applied voltage is the 500 uA meter. This meter would be a good choice for an ammeter system that makes use of a passive shunt resistor (no active components) as it will result in the lowest burden voltage. Burden voltage is the voltage across a shunt use to measure current. Note that the burden voltage drop reduces the voltage applied to the load and so in most metering systems it is desirable to have the burden voltage be as low as possible.
100 X 80 mm Meters, Full Scale Values
Full Full
Scale Scale
uA mV Ohms
44 222 5045
49.8 257 5160
50 254 5080
56.3 187 3320
1130 176 156
1200 180 150
I haven’t yet done enough testing to determine which 100 x 80 mm meter reaches full scale with the least applied voltage. More testing needs to be done on this parameter.
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- * I have two #11 Hobby Knifes on my work bench, one with a yellow roll-stopper and the other with a blue roll-stopper. I consider the yellow knife to always be my sharpest knife and the blue knife to be the less sharp knife. When I install a new blade in the yellow knife, the blade that comes out of the yellow knife is moved to the blue knife and the blade that was in the blue knife is inserted into a plastic discard box that, when full, will go in the garbage. If you buy #11 blades from your favorite retailer (online or brick/mortar) the cost per blade is about 11 cents. Don’t let 11 cents get in the way of making sharp cuts when you need sharp cuts.
–ooOoo—