Hi! 4:34. The trick (which I assume you know) to extract that white cap without causing any damage to the brushes is using a "u" shaped strong enough metal wire that should be inserted into these two small grooves around the center hole of the white cap and rotated this wire slightly until the brush arms open (a little) to allow the extraction of that cap. Thanks for the video.
Replaced belt, replaced gear C and did some cleaning, capstan not turning and wouldn't stay engaged in playback, motor was very hot. Popped the motor open and see a very dark circuit board. We'll see if I can get it working. Your videos have been so much help to me
I'm working on a 464 that engages the tape heads and then instantly retracts after pressing play. FWD/REW, Pause all work New belt, cleaned gearset. and still has the problem. Could it be an electrical motor issue? I'm having trouble sourcing the Mabuchi EG-530KD-2B that drives the pulley system so tearing the motor apart might come in handy. Thanks for the amazing content!
Could be your gear C has cracked or shattered, have you checked that? I have a video on that, also one on replacing the motor control chip in the motor you mentioned if that becomes necessary , thanks for watching.
Where can a potentiometer be attached to the circuit for a smooth full range speed control? I tried to connect it in series with the motor but a slight rotation makes a drastic change! i know it is possible but can't find so far how
Love the video. I did have a question though. I'm trying to find a replacement for my Vestax MR300 motor. It's a EG-530KD-2F CW 1600/3200 rpm. There are none to be found. Can I use the EG-530AD-2F that is CW but has 2400 rpm and adjust the pitch to that speed?? Is there a source for parts like the circuit board or the internal chips? Any help would be greatly appreciated!
I suspect the AF will work, but may not go as fast as 3&3/4 IPS? I'm not aware of anyone supplying just the internal circuit board. I just typed the part number into eBay and Google - I've bought three batches of NOS from three suppliers, so it's not like there's a reliable supplier with a big stick of them unfortunately.
Thank you for making all this content about repairing portastudios it’s been so helpful. I have been trying to repair my 488 and my motor needs replacing and I was unable to find a 530KD but picked up a 530AD on ebay instead. I read through your blog about the differences of the motors and how the black and red wires connect to the DC and ground and the other two are for positive and ground of the pitch board. Is there a way to connect those two wires to the pcb of the 530AD to control the pitch still? I am just a bit stuck on how I would wire the 530AD to make it work, even if not up to the standard speed of the original motor
Your channel and website are RIDICULOUSLY helpful! Thanks so much 👍 In your opinion, is it okay to use a potentiometer as a voltage divider to lower the voltage going to that motor, or should I use pwm? One of the things I love doing with the porta02 is using the variations in quality like a low pass filter, so i don't currently need to go faster. I can't figure out whether it's safe or not to run it at a lower voltage for the long term. Thanks ✌️ Also, that commutator looks like a lot like Hekate's Wheel. Very strophalic... Is that a word? 🤔😄
For context, I haven't actually tried either...I'd like to get into the mods/circuit bending side of electronics but to date I'm completely specialised in just getting old portastudios working again. For a voltage divider, I'm pretty sure the internal PCB screws up any linear relationship between speed and +v, and I seem to remember folks in forums etc saying they tried this approach and it didn't work? I'm not sure whether pulse width modulation would get round this, but I imagine not since any video or blog I've seen using pwm to control a motor it's always been a standard speed, 2 input cable motor. I imagine he worst that could happen is you stress out the control chip faster so if you have a replacement on hand you could give it a go, let us know how it goes?
@@Tetrakan I guess I'll have to prod at it for a while. I assumed that pwm would be the obvious choice until watching this video. I didn't realize how much was going on in there. I'm going to try to change the voltage getting to it and make sure the current doesn't go crazy. I've heard that is a problem when the voltage supply dips🤷♂️ I'll see how it goes, and let you know if anything worth noting happens. Thanks again 👍
So would modifying the components on that PCB in some way allow you to adjust the speed of the motor? I ask because I recently found a forum where an old TEAC tech claimed that the EG-530YD-2B could work as a replacement for the 530KD, but that motor is a 4000rpm motor as opposed to 3200rpm. So if it did work in the machine, you wouldn’t be able to play old tapes that were recorded with the original motor at their original speeds. So I’m wondering if there might be some way to bring the speed of the 4000rpm motor down ~20% to match the speed of the 3200rpm motor and allow playback of old tapes, provided it even works in the machine..I’m still waiting on the new motor to come in. It was $8 and I’ve got a spare 488 I’m keeping for parts that I’m going to try it on, so if it doesn’t then I’ve only wasted a few bucks and a little bit of time.
I think what you are describing might be possible, but I would have to do a lot of experimenting before I could tell you what to change, and it'd be easier, ergonomically speaking, to mount the extra/different components externally because there's really very little room on the PCB inside the motor enclosure. Was skywave the tech you mention?
@@Tetrakan it was Skywave actually. But now that you mention doing it externally, I’m wondering about just changing the pot in the pitch control? I suppose I’ll just have to do a little more research and try it out when my motor comes in. This’ll be the first time I even pick up a soldering iron, so that’s where I’m at heh thank god for your videos though man, you’re doing the lord’s work.
@@perrycolomb8206 it worked okay, but paradoxically it ended up running slower than the -KD motor by about 25%. I never adjusted the trim pot or anything (that’s something I had heard mentioned, and i imagined it being simple to do but I don’t think it is), but all the transport functions worked and it ran flawlessly, just slower. Once I got it open and got the motor in, the idea of doing extra mods to it was just too much for me so I never bothered, it was really just to find a possible alternative to the original motors; I had seen in a fb group someone who used a motor with the same rpm’s as the EG-530-KD but it would run for a couple seconds and then stop, we think because of lack of torque. So finding a motor that actually worked at all was kind of enough, especially considering how cheap they are.
The motor on my 424 MK1 was beginning to slow so I went ahead after watching your video and opened up the motor itself hoping to find a burnt out IC that I could replace. However, it appears to have a 6605 IC, an 8 legged wee beastie. I'm wondering if replacing this will correct my issues. Have you come across this before?
Because it’s a different motor in the mk 1, I’ve only ever owned one such and the motor in that unit is okay I’ve never needed to pry it open so my answer is kind of speculative but I would suspect that any motor which does 3200 rpm and has 4 input cabled will have ICs in there to regulate the motor speed which have to dissipate a lot of heat and will fail eventually for that reason, so yeah it seems likely that replacing that chip and any electrolytic caps on the internal pcb which might have dried out will resolve your issue, let us know how you get on.
@@Tetrakan well that's good to know. I'll order a chip and let you know for sure. The motor in question I believe to be the original but has no typical markings suggesting a model number etc... However, I discovered through searches that the EG 530KD 2B it's supposed to be a replacement. I happened to have a pioneer double tape deck with two of these motors and so used one, being careful to observe the correct connections. Strangely, everything plays twice as fast and on top of that, high norm slow are opposite of what they should be and the pitch control is opposite in regards to plus and minus. What do you think could be happening?
No. But same principle probably will probably resolve equivalent issues with erratic speed or not responding to user pitch controls - replace semiconductors on the motors internal PCB with new old stock parts. I’ve also successfully fitted the style of motor shown in the video in a 244, and I’m sur Ethel same thing could be done with a 246 - adaptation of the resistor network which controls the speed is necessary, I made a video about it on patreon.
Not really my area of expertise, but I suppose in principle an electric motor is just a generator in reverse, so if you turned the center of the motor (using wind power, for instance) then a very small current would be generated? You'd be much better asking a real electrical engineer this, I'm just a musician!
Interesting, im reparing a Marantz sd4000 and inside the motor i found a tiny coil on the shaft with a magnet rotating in the shaft, i think is a some type of servo motor, but one wire of the tiny coil was cutted i cant see to solder where is the cut... i need a microscope maybe..
Have you done any work or thought about how to get these motors to spin as consistently as possible? I have a Fostex 280 (Mabuchi EG-530KD-2B) and also Yamaha MT4X (SHU2L - same as Tascam 424 mk2/3), and both run fine, but with extensive testing I notice the tape speed in both machines have have an uncomfortable amount of speed error - musically speaking, the pitch will be off about 5+ musical cents when its cold, but then they settle in after a minute of use. I should note this is within the spec of the service manuals, but still. After a minute or so of disuse, both machines will back to being a little off, only to come back after about 60 seconds of playback. Not talking much, but enough to make an OCD musician a lilttle uncomfortable. And certainly enough to make an instrument performance slightly out of tune. I have disabled the pitch control pots, soldered in their place low ppm (i.e., very stable) resistors of the appropriate values to lock in the speed at the nominal setting, and also replaced the 1-turn trim pots with 4-turn versions, with tighter ppm, all in pursuit of the most stable capstan speed I can achieve (voluntarily giving up pitch control, of course). It seems I have hit a brickwall as nothing seems to improve it at this point. It's got me thinking about recapping the power supplies, perhaps to produce more stable voltage. The power supplies at this point are 25 years old (Yamaha) and/or 30+ for the Fostex. Any thoughts?
Hey, sorry it has taken me ages to reply to this comment. It sounds like you've made more in- roads into stabilising the pitch of these motors than I have! I should emphasise that I don't have any academic or professional pedigree in what I do, and even as an amateur I have very little experience in electronics beyond getting dead or dying cassette recorders to recover basic musical usefulness - so, for instance, while I do understand what pulse width modulation is and have watched a bunch of videos of circuit benders applying that technology in their projects, I've personally never used that technology. I'm also very tolerant of the shortcomings of these systems and tend to hear a little drift and warble as part of the rustic charm which distinguishes cassette from more stable recording systems. That said, here are my thoughts on what you are asking/suggesting: Recapping the PSU is definitely worth doing since these things are near the end of their recommended shelf life so you'd be adding to the longevity of the unit anyway; however, most times I've got into the nitty-gritty of the schematics of these units, the 12v rail powering the motor is coming from a voltage regulator anyway... I suppose bad filter caps might cause the voltage regulator to do more work and produce more heat, but as I understand it, if the voltage regulator should be producing a steady 12volt output no matter how leaky the big resevoir caps are. My ability to interpret competing regulator spec sheets is rudimentary, but if you have the theoretical background perhaps looking for an upgraded regulator would be a better way to purify the 12v source the motor receives, assuming that is a factor in pitch instability? Once the 12v rail reaches the motor as I understand it the motor control chip is meant to smooth out the speed, among other things? Clearly these chips have issues with heat dissipation, so mounting the servo PCB on the outside of the motor chassis and using the chassis as as a big heat sink is something I thought about. Also if the servo board was mounted outside the motor casing, the lack of restrictions on the size or shape of the board would open up scope to use a better (?) motor control chip, one still in production, so we aren't relying on finite supplies of NOS? Ultimately I fear that a lot of the pitch instability is actually mechanical in nature - physical give in how the commutator sits in its housing and interacts with the brushes. Perhaps an extant supplier could be found of a more mechanically stable motor with no internal servo, which could be used with the externally mounted, properly heat-sunk (sic) servo board mentioned above. I might be talking absolute bollocks here, but those are my thoughts. If you find a solution please let us know, and thanks for watching!
![Seungmin "그렇게, 천천히, 우리(As we are)" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/kAzmhLHePqU/mqdefault.jpg)
Hi! 4:34. The trick (which I assume you know) to extract that white cap without causing any damage to the brushes is using a "u" shaped strong enough metal wire that should be inserted into these two small grooves around the center hole of the white cap and rotated this wire slightly until the brush arms open (a little) to allow the extraction of that cap. Thanks for the video.
Thanks for clarifying that. I may not have been aware at the time of making the video!
Replaced belt, replaced gear C and did some cleaning, capstan not turning and wouldn't stay engaged in playback, motor was very hot. Popped the motor open and see a very dark circuit board. We'll see if I can get it working. Your videos have been so much help to me
Nothin beats a good ol mabuchi motor 👍
I'm working on a 464 that engages the tape heads and then instantly retracts after pressing play. FWD/REW, Pause all work New belt, cleaned gearset. and still has the problem. Could it be an electrical motor issue? I'm having trouble sourcing the Mabuchi EG-530KD-2B that drives the pulley system so tearing the motor apart might come in handy.
Thanks for the amazing content!
Could be your gear C has cracked or shattered, have you checked that? I have a video on that, also one on replacing the motor control chip in the motor you mentioned if that becomes necessary , thanks for watching.
Where can a potentiometer be attached to the circuit for a smooth full range speed control? I tried to connect it in series with the motor but a slight rotation makes a drastic change! i know it is possible but can't find so far how
Love the video. I did have a question though. I'm trying to find a replacement for my Vestax MR300 motor. It's a EG-530KD-2F CW 1600/3200 rpm. There are none to be found. Can I use the EG-530AD-2F that is CW but has 2400 rpm and adjust the pitch to that speed?? Is there a source for parts like the circuit board or the internal chips? Any help would be greatly appreciated!
I suspect the AF will work, but may not go as fast as 3&3/4 IPS? I'm not aware of anyone supplying just the internal circuit board. I just typed the part number into eBay and Google - I've bought three batches of NOS from three suppliers, so it's not like there's a reliable supplier with a big stick of them unfortunately.
Thank you for making all this content about repairing portastudios it’s been so helpful. I have been trying to repair my 488 and my motor needs replacing and I was unable to find a 530KD but picked up a 530AD on ebay instead. I read through your blog about the differences of the motors and how the black and red wires connect to the DC and ground and the other two are for positive and ground of the pitch board. Is there a way to connect those two wires to the pcb of the 530AD to control the pitch still? I am just a bit stuck on how I would wire the 530AD to make it work, even if not up to the standard speed of the original motor
Your channel and website are RIDICULOUSLY helpful! Thanks so much 👍 In your opinion, is it okay to use a potentiometer as a voltage divider to lower the voltage going to that motor, or should I use pwm? One of the things I love doing with the porta02 is using the variations in quality like a low pass filter, so i don't currently need to go faster. I can't figure out whether it's safe or not to run it at a lower voltage for the long term. Thanks ✌️
Also, that commutator looks like a lot like Hekate's Wheel. Very strophalic... Is that a word? 🤔😄
For context, I haven't actually tried either...I'd like to get into the mods/circuit bending side of electronics but to date I'm completely specialised in just getting old portastudios working again. For a voltage divider, I'm pretty sure the internal PCB screws up any linear relationship between speed and +v, and I seem to remember folks in forums etc saying they tried this approach and it didn't work? I'm not sure whether pulse width modulation would get round this, but I imagine not since any video or blog I've seen using pwm to control a motor it's always been a standard speed, 2 input cable motor. I imagine he worst that could happen is you stress out the control chip faster so if you have a replacement on hand you could give it a go, let us know how it goes?
@@Tetrakan I guess I'll have to prod at it for a while. I assumed that pwm would be the obvious choice until watching this video. I didn't realize how much was going on in there.
I'm going to try to change the voltage getting to it and make sure the current doesn't go crazy. I've heard that is a problem when the voltage supply dips🤷♂️ I'll see how it goes, and let you know if anything worth noting happens. Thanks again 👍
@@els1f P.S. I was apprehensive about googling strophalic, but I'm relieved to say the results were clean and informative
@@Tetrakan haha sorry! The runes and tats made me assume you would have gotten the terrible wordplay😄
So would modifying the components on that PCB in some way allow you to adjust the speed of the motor?
I ask because I recently found a forum where an old TEAC tech claimed that the EG-530YD-2B could work as a replacement for the 530KD, but that motor is a 4000rpm motor as opposed to 3200rpm. So if it did work in the machine, you wouldn’t be able to play old tapes that were recorded with the original motor at their original speeds. So I’m wondering if there might be some way to bring the speed of the 4000rpm motor down ~20% to match the speed of the 3200rpm motor and allow playback of old tapes, provided it even works in the machine..I’m still waiting on the new motor to come in. It was $8 and I’ve got a spare 488 I’m keeping for parts that I’m going to try it on, so if it doesn’t then I’ve only wasted a few bucks and a little bit of time.
I think what you are describing might be possible, but I would have to do a lot of experimenting before I could tell you what to change, and it'd be easier, ergonomically speaking, to mount the extra/different components externally because there's really very little room on the PCB inside the motor enclosure. Was skywave the tech you mention?
@@Tetrakan it was Skywave actually. But now that you mention doing it externally, I’m wondering about just changing the pot in the pitch control? I suppose I’ll just have to do a little more research and try it out when my motor comes in.
This’ll be the first time I even pick up a soldering iron, so that’s where I’m at heh thank god for your videos though man, you’re doing the lord’s work.
@@perrycolomb8206 it worked okay, but paradoxically it ended up running slower than the -KD motor by about 25%. I never adjusted the trim pot or anything (that’s something I had heard mentioned, and i imagined it being simple to do but I don’t think it is), but all the transport functions worked and it ran flawlessly, just slower.
Once I got it open and got the motor in, the idea of doing extra mods to it was just too much for me so I never bothered, it was really just to find a possible alternative to the original motors; I had seen in a fb group someone who used a motor with the same rpm’s as the EG-530-KD but it would run for a couple seconds and then stop, we think because of lack of torque. So finding a motor that actually worked at all was kind of enough, especially considering how cheap they are.
Thank you so much for this.
The motor on my 424 MK1 was beginning to slow so I went ahead after watching your video and opened up the motor itself hoping to find a burnt out IC that I could replace. However, it appears to have a 6605 IC, an 8 legged wee beastie. I'm wondering if replacing this will correct my issues. Have you come across this before?
Because it’s a different motor in the mk 1, I’ve only ever owned one such and the motor in that unit is okay I’ve never needed to pry it open so my answer is kind of speculative but I would suspect that any motor which does 3200 rpm and has 4 input cabled will have ICs in there to regulate the motor speed which have to dissipate a lot of heat and will fail eventually for that reason, so yeah it seems likely that replacing that chip and any electrolytic caps on the internal pcb which might have dried out will resolve your issue, let us know how you get on.
@@Tetrakan well that's good to know. I'll order a chip and let you know for sure. The motor in question I believe to be the original but has no typical markings suggesting a model number etc... However, I discovered through searches that the EG 530KD 2B it's supposed to be a replacement. I happened to have a pioneer double tape deck with two of these motors and so used one, being careful to observe the correct connections. Strangely, everything plays twice as fast and on top of that, high norm slow are opposite of what they should be and the pitch control is opposite in regards to plus and minus. What do you think could be happening?
If you can get spec sheets you could check that both chips expect the same input voltages, have the same input scheme etc?
Hey I have a eg-500ad-2B 12v 2400 ccw motor that’s going bad, do you know where I can get a replacement?
Pulley doesn’t spin freely, sometimes it runs fine then sometimes it will run then stop
Would this chip work for a tascam 246?
No. But same principle probably will probably resolve equivalent issues with erratic speed or not responding to user pitch controls - replace semiconductors on the motors internal PCB with new old stock parts. I’ve also successfully fitted the style of motor shown in the video in a 244, and I’m sur Ethel same thing could be done with a 246 - adaptation of the resistor network which controls the speed is necessary, I made a video about it on patreon.
Hello. Can I ask a question? Can mabuchi eg-530kd-2b generate electricity? And how to do it? Thanks. Hopefully you respond as quick as possible
Not really my area of expertise, but I suppose in principle an electric motor is just a generator in reverse, so if you turned the center of the motor (using wind power, for instance) then a very small current would be generated? You'd be much better asking a real electrical engineer this, I'm just a musician!
Interesting, im reparing a Marantz sd4000 and inside the motor i found a tiny coil on the shaft with a magnet rotating in the shaft, i think is a some type of servo motor, but one wire of the tiny coil was cutted i cant see to solder where is the cut... i need a microscope maybe..
Have you done any work or thought about how to get these motors to spin as consistently as possible? I have a Fostex 280 (Mabuchi EG-530KD-2B) and also Yamaha MT4X (SHU2L - same as Tascam 424 mk2/3), and both run fine, but with extensive testing I notice the tape speed in both machines have have an uncomfortable amount of speed error - musically speaking, the pitch will be off about 5+ musical cents when its cold, but then they settle in after a minute of use. I should note this is within the spec of the service manuals, but still. After a minute or so of disuse, both machines will back to being a little off, only to come back after about 60 seconds of playback. Not talking much, but enough to make an OCD musician a lilttle uncomfortable. And certainly enough to make an instrument performance slightly out of tune.
I have disabled the pitch control pots, soldered in their place low ppm (i.e., very stable) resistors of the appropriate values to lock in the speed at the nominal setting, and also replaced the 1-turn trim pots with 4-turn versions, with tighter ppm, all in pursuit of the most stable capstan speed I can achieve (voluntarily giving up pitch control, of course). It seems I have hit a brickwall as nothing seems to improve it at this point. It's got me thinking about recapping the power supplies, perhaps to produce more stable voltage. The power supplies at this point are 25 years old (Yamaha) and/or 30+ for the Fostex.
Any thoughts?
Hey, sorry it has taken me ages to reply to this comment. It sounds like you've made more in- roads into stabilising the pitch of these motors than I have! I should emphasise that I don't have any academic or professional pedigree in what I do, and even as an amateur I have very little experience in electronics beyond getting dead or dying cassette recorders to recover basic musical usefulness - so, for instance, while I do understand what pulse width modulation is and have watched a bunch of videos of circuit benders applying that technology in their projects, I've personally never used that technology. I'm also very tolerant of the shortcomings of these systems and tend to hear a little drift and warble as part of the rustic charm which distinguishes cassette from more stable recording systems. That said, here are my thoughts on what you are asking/suggesting: Recapping the PSU is definitely worth doing since these things are near the end of their recommended shelf life so you'd be adding to the longevity of the unit anyway; however, most times I've got into the nitty-gritty of the schematics of these units, the 12v rail powering the motor is coming from a voltage regulator anyway... I suppose bad filter caps might cause the voltage regulator to do more work and produce more heat, but as I understand it, if the voltage regulator should be producing a steady 12volt output no matter how leaky the big resevoir caps are. My ability to interpret competing regulator spec sheets is rudimentary, but if you have the theoretical background perhaps looking for an upgraded regulator would be a better way to purify the 12v source the motor receives, assuming that is a factor in pitch instability? Once the 12v rail reaches the motor as I understand it the motor control chip is meant to smooth out the speed, among other things? Clearly these chips have issues with heat dissipation, so mounting the servo PCB on the outside of the motor chassis and using the chassis as as a big heat sink is something I thought about. Also if the servo board was mounted outside the motor casing, the lack of restrictions on the size or shape of the board would open up scope to use a better (?) motor control chip, one still in production, so we aren't relying on finite supplies of NOS? Ultimately I fear that a lot of the pitch instability is actually mechanical in nature - physical give in how the commutator sits in its housing and interacts with the brushes. Perhaps an extant supplier could be found of a more mechanically stable motor with no internal servo, which could be used with the externally mounted, properly heat-sunk (sic) servo board mentioned above. I might be talking absolute bollocks here, but those are my thoughts. If you find a solution please let us know, and thanks for watching!
thanks!