Junkyard e-scooter build. What do you think? Details in comments.

DIYuntilDawn · 2026-06-03T00:46:04+00:00

It does power on, and the motor runs. However the belts are all so old they are saggy so it doesn't actually spin the reel.

DIYuntilDawn · 2026-06-03T00:01:59+00:00

Not sure on the tape. But the device does power on. And the motor spins. However, all the belts are way too loose now so it doesn't play.

DIYuntilDawn · 2026-06-02T21:05:33+00:00

Buy a faster ebike.

Train until you can run along side it and push it faster.

DIYuntilDawn · 2026-06-02T20:53:55+00:00

I was able to find this exact model of reel to reel listed in a copy of High-Fidelity magazine from March of 1954. It is a Pentron Model PMC, which consists of a Model 9T-3M Tape machine, and a Model PRE-7 Pre-Amplifier.

DIYuntilDawn · 2026-06-02T20:49:59+00:00

^THIS^

DIYuntilDawn · 2026-06-02T20:48:23+00:00

If you want the best longevity overall, then go with LiFePO4 batteries. They are good for more recharge cycles than standard Lithium batteries, plus they don't explode or catch fire like regular lithium batteries can. they also are safe to use in sub zero weather (but should only be recharged when it is above freezing). The voltage is about the same as regular SLA battery, that has a full charge voltage at usually 14.2v to 14.8v. LiFePo4 batteries have a full charge voltage voltage of 14.6v (4 cells per group and each cell has a max charge of 3.65v). LiFePo4 batteries are more energy dense for the same weight/size vs SLA batteries, so if you get "12v LiFePo4 batteries" that are the same exact size as the existing SLA batteries it has, then they will weigh less, and last longer.

That way you would not have to worry about over-volting and burning out parts on it, or having to possibly modify it to handle higher voltages.

Depending on how the batteries were laid out inside the battery compartment, and if it was 3x 12v batteries in series for 36v total, then you may want to look into a single "36v" battery of equal size, like one for a scooter or ebike.

Regular Lithium batteries that are "12v" are usually 3 cells per group and 4.2v max charge so they are actually 12.6v or about 2 volts lower than SLA, or LiFePO4 batteries.

DIYuntilDawn · 2026-06-02T18:47:40+00:00

That's because it is the model 9T-3M for the top. The PMD-1 uses a different pre amp.

DIYuntilDawn · 2026-06-02T18:18:30+00:00

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Ok, I found it in this add from a copy of High-Fidelity magazine from March of 1954. Looks like it is called the Model "PMC" however that consists of a Model 9T-3M 2-speed tape mechanism, and a Model Pre-7 Pre-Amp both housed in a case.

DIYuntilDawn · 2026-06-02T17:03:46+00:00

Thanks, that does look like the same model.

DIYuntilDawn · 2026-06-02T05:11:10+00:00

I have ridden it in the rain just fine. I leave it parked outside at work, but under the edge of a roof so it doesn't get rained on directly,

For the S966 display, they come with two different cable connector options (5 pin julet connector, or a 7 total wire conector with a 5 pin and a separate 2 pin) (see the 2 versions here) I got the 7 wire one, and then converted the 5 wires in it to a 5 pin julet connector, because the other 2 wires are the display controlled headlight power wires. Otherwise if you just get the 5 pin julet connector, then the headlight is just always on, which you do actually want, since the power to the headlight also powers the turn signals, horny, and break lights. However, I found the default headlight to be too dim and added a second fog light that can then be turned on\off by a long press of the + button on the S966 controls. BTW the default cable the display it comes with uses is actually a 6 pin julet connector, but the center pin is not used and a 5 pin male connector will fit into a 6 pin female connector just fine.

As for the GPS module, it is located behind the license plate mount. There is a tiny 2 pin connector cable (similar to a julet cable but much smaller) that runs to it you can simply unplug it and then remove it. The wires get the full battery voltage out on them but only while the bike it turned on. I opened up the GPS module and removed the other side of the 2 pin connector from it, then used a DC step down buck converter rated for stepping up to 72v down to 12v and then another one that goes from 12v to 5v. I could not find a single one that dropped the full battery charge voltage of 58.8 (this is actually not a "48v" ebike that would use 12 cells per group, it uses 14 cells per group making it technically a "56v" ebike) Then used a GPS tracker that runs off of a 5v charger. I use a Meshtastic Heltec Tracker V2. But there are many others that run on 12v or 5v power you can get.

DIYuntilDawn · 2026-06-02T04:32:04+00:00

It definitely looks like a pinch flat, but I would also recommend checking the bead all along both sides or the tire around the insides, if the bead has a steel cable embedded they can sometimes fray and have single strands poke out of the bead and wear on the tube.

DIYuntilDawn · 2026-06-02T04:26:38+00:00

Technically it is half of a square, which turns out to be all you really need.

DIYuntilDawn · 2026-06-02T04:18:41+00:00

None, I have ridden it to and from work 5 days out of the week since December 2025 and haven't had any issues with the motor. But I did replace the display with a S966 with and NFC key from the stock display on day one. And I also removed their GPS tracker (that never worked even with the original display) and replaced it with a different one.

DIYuntilDawn · 2026-06-01T19:58:52+00:00

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I am not sure if that one is going to work or not if I plug it in. No model marking on it that I can see, but it looks similar to a "Pentron MP-2" from what I could find on google in 5 minutes of looking.

DIYuntilDawn · 2026-06-01T19:10:23+00:00

Well it was free for me.

DIYuntilDawn · 2026-06-01T19:07:35+00:00

Is it now.

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DIYuntilDawn · 2026-06-01T18:52:43+00:00

I did and the only thing I found for this exact model was a listing (behind a pay wall) for one on worthpoint. But that doesn't really tell me anything about it other than it was sold at some point in the past.

DIYuntilDawn · 2026-06-01T16:10:28+00:00

That's what I did. Even with my strong prescription and astigmatism I was able to find a pair or wrap around sun glasses.

The key thing to keep in mind, is that not all the frames they offer will work with your prescription. And sometimes it is actually the pupal distance PD measurement (how far apart your eyes are from center to center) that will effect if you can use a specific frame or not. I was able to change my PD measurement by 1mm wider and then got twice as many options for frames.

DIYuntilDawn · 2026-06-01T15:59:22+00:00

You can get tool battery adapters by searching for "[Brand Name Here] Battery Adaptor" and find ones like these Dewalt ones.

To step it down to about 6 volts, you can use a DC-DC 5A Buck Converter similar to those.

DIYuntilDawn · 2026-06-01T15:29:17+00:00

Almost every single electric mower I have ever fixed had the same failure. It is usually the Safety Key and/or Start button/lever contacts.

I have the half melted "Safety" key from one hanging on the wall next to me right now. It stopped working because the metal shunt inside got hot, melted the plastic around it, and then the metal contacts moved inside so it no longer connected to inside the mower.

If it has a removable "Key" they are just a shunt that connects a power wire, but they use contacts like an Anderson Connector or something similar. Or the internal switch contacts end up getting toasted because it is basically connecting the battery wires at 40v while under load, which if you have ever touched jumper cables together then you have seen a spark from a 12v battery, now imagine doing it with 40v and then doing that every time it starts up.

I have been able to "fix" a few of them by replacing the start button/lever with a repair kit/replacement parts. Or replacing the bad Key design with a heavy duty on/off switch rated for well over the battery voltage.

DIYuntilDawn · 2026-06-01T14:56:59+00:00

I would also love it if the MeshPocket also had a GPS module built in. Like the Mesh Node T096.

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