Teunkie Van Der Sluijs

Ooooh, that is very interesting. I have not come across the models with inbuilt light meters, nor constant speed motors with that little box on the side. That might well be the transistor? A person likely to be able to tell you will be Sean Charlesworth, who was head repair at NYU looking after their sizeable 16S collection. I'm afraid I cannot advise you on the power supply with a view to the light meter. But I think you're absolutely right to err on the side of caution; light meters are sensitive bits of equipment. Both the variable speed motors and the governor controlled constant speed motors were kind of reliable in their frame rate. But the most reliability requires a crystal sync motor - although that transistor model was apparently pretty good - good enough for the B-GS to run sync sound, in any case. As regards power supplies, the camera itself can take a bit of range: 6V for 18fps, 8V for standard 24 or 25 fps, and up to 12V for 48 fps. Do not use 12V with the 400ft magazine unless you have the magazine torque motor altered to take this. Also, it's not advisable to run the camera at 12V for long amounts of time and without film; it can really damage your motors. I'm sure you'll have come across the options people use most frequently. A common DIY solution is a rechargeable RC battery, which tends to come in 8.4 V. They're fairly inexpensive. See this topic for more info. That's the set-up I'm using at the moment. I have a couple of issues with it, though. One is that these kinds of batteries don't hold charge for very long, and likely only last a few years. They sure hold enough charge to run the camera for a decent amount of time, but if you're needing to replace them every few years, isn't it better to find a more durable solution? Also, my RC battery fluctuates, from 7.8 to 9.4 V. Might be age, but it's not great. I could technically install a voltage regulator to at least step down a higher voltage to an exact 8V, however, that doesn't allow to boost up, plus most voltage regulators require a minimum difference of 1.5 V between input and output to be effective. Michael Leake has a homebuilt battery pack, which he explains in this forum post here. It looks like he uses a buck convertor voltage regulator, judging by the photos. I think if you have V-Mount batteries lying around for other purposes anyway, that's a really solid way into powering the camera, but it's not a solution I've come across a lot in this forum, for whatever reason. Alvin Morris demonstrates a version of it in this video here. He's using a Tilta plate. There are a few other manufacturers who offer 8 or 8.4V outputs on their V-plates, but the Tilta is definitely the better rated one. Theoretically, you could get a basic, cheap V-mount plate that doesn't output 8V, and install a voltage regulator between battery and camera to get the exact output you want, but I don't what you'd need to take into account with a view to the camera's impedance. I imagine the boards at Stack Exchange might provide some wisdom...? Let me know how you get on. Has yours been converted to take XLR input, or are you one of the lucky few to still have the original ARRI plug on the back?

Hi Thomas, I have exactly the same model (16S/B-GS) and been fashioning new power supplies for it the past couple of weeks. As regards motors, Arri themselves produced the Variable Speed Motor (probably the most common one still in use), running of 8.4 V battery power for 4-48 fps, and then two types of constant speed motors, known as Governor Controlled Motors, one for 24 fps, one for 25 fps. They also take 8.4 V, although technically, you could power them with 6V car batteries at the time too, for around 18 fps. For the B-GS models in particular, Arri later produced a new model of Governor Controlled Motor, with a transistor (339 301) which ran at pretty reliable 24 fps, allowing for sound sync work. At a later point, Arri produced their own crystal synch motor, mains powered. These require the 42 V transformer to output a particular type of motor. There's one or two on eBay right now, and I'm fixing up an old one (which seems intent on running on a rather unusual 26 fps). See one at https://www.ebay.co.uk/itm/ACCESSOIRES-pour-CAMERA-ARRIFLEX-16-mm-Moteur-Synchrone-42V-Bte-dalimentation8V/200768423141 Tobin were third party suppliers and they're no longer around, although the motors still pop up every now and then on eBay and equivalent sites. They produced both variable (TM models) and constant speed motors, as well as crystal synch (TXM models). Jensen were another supplier, but a bit less common than Tobin, and harder to find these days. The main thing to look out for is your power supply. Unless I'm wildly mistaken, the Jensen motors take 12 V, and if you're running the 400 ft mags with a torque motor not fitted for 12 V, you're at risk of ruining that torque motor.