
I thought it would be fun to write up what I could about this relic from a time before CDs when Star Trek II: The Wrath of Khan and E.T. the Extra-Terrestrial were both in theaters.
Introduction

Manufactured by Prince Tsushinkogyo Ltd. in Japan, the tuner has the model name of AccuPitch 440 from Guild and HU-8100G by Arion (Arion tuners are also called Micons). The Piggy version seems to be nothing more than a rebranded Arion because it has the same HU-8100G part number.

I do have to say that I find it fascinating that just looking at the two of them side by side, that I am drawn to the one on the right because it looks better. Why? Because of the Guild logo. I think I may be in too deep.
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The guild catalog copy states that the tuner has the following features:
- A tone generator and a tuner featuring a precision quartz element & microprocessor

- Can tune guitars, basses, banjos, violins, mandolins, etc.
- Compact size-fits into instrument case accessory compartment
- Metered and LED readout
- Accurate to one cent (1 cent = 1/100th of a semitone)
- Input and output jacks enabling it to be put “in line” with electric instruments
- Built in 7 tone generator, including A-440, so any instrument can be tuned
- Battery check and A-440 calibration screw
- Background noise only slightly affects readings



And no – you can’t have any of them.
Operation

This tuner can be used as a standalone device where you plug the guitar into the input jack, pluck (pick, more likely) a string and read the results on both the analog needle and the LED display. The downside of a tuner like this is that you have to choose which note you want to tune or you won’t get any useful results and it only has six options that correspond to the strings on a guitar in standard tuning.

Technically, you could tune to a half-semitone up or down by using the analog scale which is graduated on the bottom in 10-cent increments with -50 and +50 clearly indicated. Unfortunately that means that a tuning as simple as E♭is not possible because the best you can do is E♭and ½ which is a bit nutty unless you’re into microtonalism or early Van Halen albums.

The top slider switch lets you chose from the six standard-tuning strings and will function in both TUN mode and the SOU mode, which brings us to the bottom slider switch.
The bottom slider has four positions labeled:
- OFF
- BAT (A440)
- TUN
- SOU

BAT (A440) is both a battery meter and a tone generator but since this tuner does not have a speaker the tones are generated only through the Output jack. When the battery is fully charged, the meter will be in the center as shown in the last couple of images. When plugged in, that A440 tone that we all know and love is sent to the amps for the audience to enjoy.
TUN is short for Tuner and is likely the mode in which the average guitarist would find themselves most often. In this mode, with the upper switch selecting the proper string, a note is played on the guitar and the needle and LEDs indicate if you are within 50 cents of the note in either direction (sharp or flat). The LED seems to consider “in tune” to be anything within 50 cents plus or minus the actual frequency being tested which makes the LEDs 100% useless in my mind. Note that unlike many modern pedal tuners, this unit does not mute the signal while tuning so your audience can enjoy your tuning almost as much as your bandmates.

Also, I guess you could use the microphone feature to tune things like orchestral instruments provided that you want to tune them to a guitar’s standard tuning since there is no capability to tune to A400 aside from just matching the tone from the BAT (A440) setting by ear—which requires an amp since there’s no speaker.
[dropshadowbox align=”right” effect=”raised” width=”” height=”” background_color=”#ffffff” border_width=”1″ border_color=”#dddddd” ]Accupitch 440 Tones
[/dropshadowbox]SOU is short for Sound which should really be labeled TON for Tone Generator, though I’d imaging TON would easily be confused with TUN. In this setting, the unit does nothing but generate tone so that you can tune by ear. Again, there is no speaker, so tuning using this method requires cabling the tuner up to an amplifier. When in this mode, the LEDs light in sequence from left-to-right repeatedly to indicate that you can’t use them for tuning. Or because it’s cool. You can hear the tones generated in the attached sound clip which includes, in order, E,A,D,G,B,E and A-440. Note the sort of slow ramp-up on the last A-440 sample. This was fairly common in my testing and seems to be indicative of how this ’80s tech seemed to function.Gooey Gadget Guts

In order to gain access to the battery, the entire back comes off with a slight push of a latch. I should note that the entire case is plastic and holds together with plastic tabs, so I imagine it would be very easy to break thus making these old tuners even harder to find in good condition if you’re on the hunt for one. With the back off, I was stymied by rubber foam that was glued to the back of the circuit board. Of course, that didn’t stop me.


I was bummed to discover upon unpacking this tuner that one of the LEDs was not working. With the guts out I’m happy to say that I discovered the problem to be a bad solder joint on the offending LED which I was able to repair. Man, if there’s one thing that makes me happy it’s being able to bring old electronics back to life.

A quick note to anyone who decides to do this: Be careful when reassembling the case because the LEDs, if not lined up with their holes, may get crushed or have their legs bend to the point of breaking which I think might be what happened to mine. Also, there’s a little plastic battery enclosure that you can see on the top left of that last pic. If you put the whole thing back together and the battery is flopping around in the case, you probably forgot to snap that back into place like I did.
Real Use
In practice, this old tuner (and I’d imagine any tuner this old) is a bit annoying, especially when compared to the myriad ubiquitous tuning options available to guitarists today. This thing would have been cool as hell back in the early ’80s because there really wasn’t anything else. When I was in high school band we had one of those huge Peterson strobe tuners (Actually ours was a Conn like this one) and that was the first tuner I’d ever seen. For years I tuned my guitar with an A440 tuning fork that stayed in my case. I still have it in the drawer in my home office in case I need to tune my guitar after the apocalypse. We’ll see who’s prepared.
Today I have an Axe-FX III that has an amazing tuner built in that I can reference from my MIDI foot controller and that I can also use on a laptop via USB. I also have one of those little Super Snark tuners in my case that I never use because the one in the Axe-FX is so good. My daughter has an acoustic with an on-board tuner built into the preamp. When I play through a real amp I use a small pedal board that has a kick-ass Turbo Tuner that I adore. Hell, I even have the Peterson Strobo-Tuner app on my iPhone which works with the same visual cues as that old Conn I used in high school. That iPhone app is my go-to with acoustic guitars because it’s always on me. Hell, I could buy the current Guild Tuner if the desire struck me.


My test consisted of the guitar being connected to my Rygol Oscilloscope with a BNC-to-alligater-clip that I clipped to the contacts within the phono jack on the end of my Lava cable. This first output is the guitar right into the oscilloscope. I then proceeded to bang on the strings Pete Townsend style in an effort to produce as much signal as possible. I did this a few times and selected the highest output I recorded, which is shown here. There are two measurements on the bottom but I’m going to be looking at the first one: Vpp (Voltage peak-to-peak) which is the highest amount of voltage from top to bottom. The absolute highest signal I could produce was 30.0V which is 15V above the center and 15V below (each square is 5V in this output).

Finally, not only does this tuner not have true-bypass, it simply cannot be bypassed! In other words the tone-suck remains even when the tuner is turned off, so the feature that says Input and output jacks enabling it to be put “in line” with electric instruments while technically true, is really not in practice because the tuner has a pretty significant affect on the signal.
Conclusion

First of all, you can get generic ones for $20 online, and honestly that’s too much because for $20 you can buy a Snark at any music store. Actually, you can probably buy two. Secondly, here in the middle of 2019 even $9 tuners are far more advanced than this old thing. As a piece of ’80s Guild nostalgia, though, it’s pretty cool, even if it will spend the rest of its life sitting on my bookshelf.
And no, you can’t have mine.
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A very interesing and amusing review on this tuner – thank you!
I found your page as I have the Arion version of this tuner (which I still use as I am too tightfisted to buy a new tuner) but it is a pain to use, for the reasons you state. I always wondered what the SOU setting was all about (I guessed it was short for Sound) but have never plugged an amp into the output so that explains it!
Incidently, there is a Piggy version on ebay at the moment: https://www.ebay.com/itm/184968236361?mkrid=711-53200-19255-0&siteid=0&mkcid=1&campid=5335816800&toolid=10001&customid=bgp&mkevt=1
Kind regards, Ian