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Numark PT-01 modding thread


Guest rasteri

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Guest rasteri

Yeah NIMH's have a nominal voltage of 1.2 but when fully charged they're closer to 1.5. The PT-01 should be OK running from 7.2v or less, so use a 6-cell pack and you should be gold.

 

You might actually get away with using a 2S lipo battery if you want even better energy density.

 

Or, even better, you get boost converters (google XL6009) that will convert a lower voltage up to a rock-solid 9v. So you could have (for example) a single large lipo cell at 3.7v powering the PT-01.

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Hmmmmm interesting..I've heard a lot about lipo batteries but have never used them for anything. I know you need special chargers for them or they can get super gnar gnar..I always try to make packs for devices that I want to have a longer lasting charge like a portable speaker or a vape mod or something... Would a lipo be a better battery type for use instead nimh rc packs or lithium 18650 cells?

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Buying rechargeable d cells would totally be the logical thing to do;) but at moment I just gotta be careful how I spend money..my wife has been having problems with her health this past month and has taken leave from work.. And with a family of 5, it has been just as difficult to make extra money as it is to spending it. Hence my reusing and repurposing;p

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Would a lipo be a better battery type for use instead nimh rc packs or lithium 18650 cells?

18650s are normally lipo too. Either will be fine.

So I made one 8.4v nimh pack and installed with deans connectors..seems to be running fine. Could I run 2 of these packs parallel at once to double the amperage but keep the same voltage?

 

https://instagram.com/p/BQgJ3nthdif

 

I also have a couple 18560 battery sleds that I'm going to put deans on to try 2x18650's since that'll put the pack at 8.4 as well..

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The battery leads bypass the voltage regulator so you'll be fine.

 

oh interesting, i've been running my 3s lithium pack from the leads. :o

 

so far nothing has exploded lol... but maybe ill move it

 

 

 

Would a lipo be a better battery type for use instead nimh rc packs or lithium 18650 cells?

18650s are normally lipo too. Either will be fine.

So I made one 8.4v nimh pack and installed with deans connectors..seems to be running fine. Could I run 2 of these packs parallel at once to double the amperage but keep the same voltage?

 

https://instagram.com/p/BQgJ3nthdif

 

I also have a couple 18560 battery sleds that I'm going to put deans on to try 2x18650's since that'll put the pack at 8.4 as well..

 

 

2 packs in parallel will keep the same voltage but I'm not positive that is the best way to go about it. With lithium batteries I usually do a series of parallel groups, but this is because I need to be able to monitor the voltage of each group to charge them safely. I'm using a 3-series over charge/over discharge/short protection board and 6x 3000mah 18650 batteries (3 groups of parallel the put those into series = 12.6v 6000mah).

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Anyone use a PWM DC motor speed controller for their pitch? I ordered one from amazon and its awesome but some reason it doesn't work when powered by the batteries. I removed it and went back to the resistor method but I want it to work.... plus I already drilled the hole for the knob haha.

 

The module I used is here https://www.amazon.com/gp/aw/d/B010JNKFKM/ref=yo_ii_img?ie=UTF8&psc=1

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Anyone use a PWM DC motor speed controller for their pitch? I ordered one from amazon and its awesome but some reason it doesn't work when powered by the batteries. I removed it and went back to the resistor method but I want it to work.... plus I already drilled the hole for the knob haha.

 

The module I used is here https://www.amazon.com/gp/aw/d/B010JNKFKM/ref=yo_ii_img?ie=UTF8&psc=1

 

im thinking that its the minimum voltage (6v). I believe that the motor runs at max 6v. This is the one I tested and it works but very inconsistent rpms at low speeds https://www.amazon.com/uniquegoods-1803BKW-Controller-Adjustable-Driver/dp/B00RYKR83Q/ref=pd_sbs_60_1?_encoding=UTF8&psc=1&refRID=K9TXZF5VWMAC0G24MAY2

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Are you people wiring the PWM module into the motor out or directly into the 9v supply? (If you're not doing the latter you really should be).

 

I wired it straight to the motor out. I will try directly from the 9V and see what kind of results I get.

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I wired it to the 9v, and the 12v both perform horribly at similar speeds. Since I was doing so much testing anyways I thought to make it easier on myself and used screw terminals for the 12v and 9v.

 

Edited by evil98
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I wired it to the 9v, and the 12v both perform horribly at similar speeds. Since I was doing so much testing anyways I thought to make it easier on myself and used screw terminals for the 12v and 9v.

 

Whats the part with the screw terminals that you've attached to the regulator great idea very handy

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First post... hi, I'm from Bavaria (near Germany). I haven't owned a turntable since ages, and just recently bought a Technics SL 1200 from a friend, just to be able to listen to my old records again (mostly HipHop from the 80s/90s). For unknown reasons I stumbled upon that PT01 Scratch video on Youtube, and after reading a bit a few weeks ago. Three weeks ago, I bought one, more out of curiosity for the general concept of a portable turntable with these in/output possibilities, than to actually "go wild" at scratching.

 

As for "just having fun", I am disappointed about quite a few things, i.e. that the "scratch button" does not affect USB-out, or that it does not allow a reasonable usage of headphones. All the inputs and outputs seem to be connected in the most stupid way. I understand very little about electronics, but as far as I have seen, electronic issues (or fader technology) are being taken care of by quite a lot of amazing people and projects, so I'll simply "keep listening" here...

It surprised me a little bit to see that most people focus on, and try to improve, the PT01 "gimmicks", but very few have a deeper look at the turntable itself. After all, it's the PT01's "heart". So far, I have adressed some major aspects about the turntable that I personally disliked: The platter's "soft" feel, and the questionable needle.

But first, I swapped the stock loudspeaker for a Visaton one. Visaton are famous in the German hifi community, and at only $5, this excellent speaker is a steal. It's not a "day and night" difference (after all, we are speaking about tiny 2" acting as a "fullrange"), but clearly noticeable. I had a few of those speakers left-over from other projects anyway, and with a little adapter ring, it's an easy upgrade.
(Link to adapter piece: https://www.youmagine.com/designs/adapter-piece-for-numark-pt01-and-visaton-frs-5-xts)

 

 

 


The majority of the turntable platter's "flex" bases on a weak connection from the (bronze) bearing to the flat platter surface. It's basically "a short tube connected to a round plate", without any reinforcement ribs at all. So I designed and 3D-printed a reinfocing part that I glued to the platter. The "lotus flower" design is a result of trying to "frame" and expose the existing mini-ribs so that I can put on glue from the outside, maximizing the contact area of the additional part to the platter. It worked as expected, but however didn't really satisfy me. This issue remains to be addressed...

 

 

 

I finished building my very own tonearm yesterday. The PT01 tonearm's geometry is excellent for playback of records, especially 7" size, bytheway, but I hesitate to expose any valuable record (i.e. old 7" from the 60s) to that needle. So I took a Shure M44-7 system and adopted it to my PT01. In contrast to other PT01 tonearms I have seen, mine does not require any springs or rubber bands. Plus, it offers a few "features", like an adjustable counterweight, and an "anti-crash" device.

The tonearm consits of six 3D-printed parts, where two couples were glued together. Glueing and machining required some 3D-printed tools as well, so there are quite some "hidden efforts" involved. Compared to the stock needle, the Shure is incredibly heavy, so counterbalancing with a metal weight was a real challenge. After all, I didn't want to exceed the "footprint" of the stock system (i.e. a longer counterbalance arm would ease things a lot, but then it would stick out to the side when You're playing), and still be able to use the turntable cover. Last but not least, since we are speaking about a "mobile device", I wanted my tonearm to be as lightweight as possible.

This build was meant to be a "proof of concept". I wasn't concerned about the essential function (in the end, it's just a tiny sea-saw), but I was afraid about noise (i.e. the carbon composite tube acting as an "antenna" and messing with the needle signals), or audible resonances. But it works perfectly. I have read about the low volume output before, but I wanted to see that first hand before adding electronics...

 

https://www.youtube.com/watch?v=7-xYZn0O3IU&feature=youtu.be
https://www.youtube.com/watch?v=upTMMfa7--o&feature=youtu.be

 

 

 

 

That's it for now, first episode of "the unattended freelance engineer and his Ultimaker". Next thing will be a new platter...

 

r

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The tonearm looks great 👍🏻

 

Isn't it easier to just place a teflon coated plastic ring around the outer edge under the platter to take up the space so there is only a 1 mm or less gap between the platter and the bottom of the platter recess ?

 

Like the platter bars that are available but cleaner looking.

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Isn't it easier to just place a teflon coated plastic ring around the outer edge under the platter to take up the space so there is only a 1 mm or less gap between the platter and the bottom of the platter recess ?

Yes, it would have been easier. But it only fiddles with the sympton, not the problem cause.

 

I just adjusted the PT01's 33 and 45 settings with the help of the Dr. Feickert record/app. 33 as well as 45 were set ~1.2 rpm low. Flutter at 33 rpm is ±1.3%, bytheway, at 45 it's ±0.8%.

 

r

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