Tascam Portastudio 414 mk1 playback, ffw, rew problems

[Marco344]

Hi there,

Recently I bought a 414mk1 I picked it up from the seller who let me try it out before. He used a 14V power adapter and everything worked well, when I brought at my place I used an universal power supply with the correct specifications (12V 1.5A and central polarity negative) but It happened that the mixer worked fine but when I tried to play a cassette the playback had a "wobble" effect and it was very slow, moreover also the reverse and ffw were really slow and they stopped before finishing their task.

Since I'm new to cassette recorders I was wondering if it depends on the power supply or it is a matter of belts, motor, etc? I also thought that the recorder worked normally with the 14v supply because of it was receiving more voltage as needed.

Please let me know if you have any tip.

Thanks in advance!
-Marco

 

[SkywaveTDR]

14 Vdc does not belong in the deck so if there was a part like the motor getting too much voltage then it could be damaged. A wobble symptom is usually a lack of oiling in bearing and bad belt. The question is when was the belt changed last? At the same time the belt is changed was the capstan bearing oiled. Bearing with no oil do not work very well and even regular oil is not as good as the stuff I have come to use. The fast wind is related to the capstan motor and may be needing lubrication as a lot of stuff happens off that one motor. Idler tires get worn down and some crack so they are replaced here all the time. The ones I put in last a lot longer and have a 10 year shelf life. They are not regular rubber.

 

[Marco344]

Thanks for your reply.
The seller told me that he bought the recorder some months ago but he didn't know if the belt or other parts were changed. Saying that I would need some tips regarding the belt: do you think that in an universal belt kit (50 pcs) I could find the right ones? If not, is there some indication of the measures? (The same question goes for the idler tires)
In addition, could you suggest me which oil is better to use?
Thanks in advance.

 

[SkywaveTDR]

I don't buy belt kits or any belts from E bay as most the time they are wrong. I get belts from my fellow Dan who is a PRB distributor or from Consolidated Electronics but you need to know the size. It all depends on what size you need. The 488 Mk II uses a 8" belt but that doe snot mean yours does. I take the old belt off and notice it condition. I then pinch it together and measure it on a metal rule- the IC is 2 times that which you measure. Then I use a caliper to measure the width and thickness. Then I go over to consolidated and order a belt the same width and thickness as much as possible but reduce the measured size by 6% because the old belt is stretched. This is the website that you need to order from.
http://www.ceitron.com/passive/belt.html
If you measure between sizes always get the smaller belt as a belt too large will not do the job.
Oils is a opinion type item but I can tell you that since I started using AMSoil Signature 0W30 synthetic oil in decks I not only feel the difference but I can measure it in the wow and flutter figures of a decks. my first one I used it on was an old Teac A2000R. When I measured the wow and flutter I thought there was something wrong with my set up as the 2000R never could do wow and flutter this low. It was .02% but no matter what I checked it kept that value all through the tape and it was true. I have since that time used it on all kinds of decks and get similar results. The stuff can be had a some auto stores or even off Amazon I think. It is about $13 for a quart but this is the real thing and wouild do wonderful on all kinds of uses. Synthetic oil does not break down like the organic stuff does as it is designed with long life and high temps use.
I put the AMSoil on the Pinch Roller bearing- never did I see a pinch roller free spin on the shaft as if it was a ball bearing.

 

[Marco344]

Thanks a lot for the tips and for the accurate answers. I have a last question, I'm waiting for the items and tools to arrive so I haven't do any job to the recorder but today I turned it on and after a couple of minutes the capstan motor suddenly stopped working. Do you think is it due to the previous owner's mistakes (14 vdc supply instead of 12 vdc) so it is damaged and it need to be replaced? or maybe did it happen because it needs lubrication?

 

[SkywaveTDR]

Old equipment made for profit does not have all the greatest of parts in them. It is hard to tell if the over voltage did damage or if the motor just stopped working as it is old. There are electronics parts inside the motor as it is a voltage stabilized motor. The problem is the the original motor is not available and so you need to find one that will work. I think a EG530YD-2B or maybe a 9B if the 2B can not be found. As I remember though the speed control need modification to get the right speeds as original motor was 3200, 1600 and the new one is 4000, 2000RPM. First before assuming the motor is bad check for the 12 Vdc going into it. It is possible that the motor will run without the belt on and if so then the mechanism has a frozen up part that is stopping the motor. That is why these can not be repaired with just a belt as the old grease needs to be cleaned out and Lubriplate 105 put into the mechanism.

 

[SkywaveTDR]

The oiling of the capstan bearing is very important and I take the flywheel off the deck and clean it then oil well the capstan bearing. When I put the flywheel back on the capstan shaft needs to have oil cleaned off of it after deck or mechanism is together and I use cotton swab with denatured alcohol for that. The flywheel should turn very easy then and if it does not then you need to go looking for why it does not. Low end mechanism without cam motors or solenoids make use of flywheel assist method which make more load on the capstan motor. When putting capstan shaft in bearing work it in and out to distribute the oil evenly in the bearing. AMSoil 0W30 signature series synthetic car oil is what I have been using with great results.