Fixed Broken Intricate Parts In Mechanism In Sony Walkman TCM-150
This Sony TCM-150 Cassette Player (Walkman) was brought by a regular customer from a faraway place. This was one among the six sets he brought. The complaint was that he tried to change the belt and he could not do it. As usual, I opened the set and did not find any dust, probably cleaned by the customer himself. I noticed that some parts of the mechanism were broken.
Probably due to unskilled handling. The stem of press switch release spring had come out:
So, I had to dismantle the set completely, before which I downloaded its service manual from the web, De-soldered the motor, head, speaker and mike connections, after taking clear snaps of these.
Then I first fixed the broken stem in its place using superglue and Fevibond and inserted thin cut leads of components into it from the other side, for which I had to dismantle the head unit. Since the up and down movement of the head should not have any obstruction, I made sure that there were no protruding portions. Used soldering iron to flatten the plastic part, applied superglue that side also and ground the rough area ensuring that it is strong enough to hold the stem, as a tension spring will get seated on it on the other side. See how it is fixed back like the original:
Then took up the following part, which was also about to break from its base and come out:
I removed the spring and fixed the base with superglue. Then drilled a small hole from the other side. Since it was hollow, I used a small screw and tightened it and applied superglue for a strong hold. Then fixed the spring after waiting for strong bonding. Then put the belt on the motor:
In the process of fixing the broken parts, I had to remove one of the wheels, which had a strong spring with three fixing/locking washers:
While I took care not to allow the spring to jump off while removing the washers, never did I think or realize how difficult it was going to be to fix it back. Well, every time I tried to hold the spring pressed down and put the large holding washer, and then the smaller white washer, it just slipped out. When I tried using tweezers, the spring jumped off with the washers and I almost lost it! This ‘Spider and Bruce’ attempts continued several times without any success.
Finally I used a tailor thread and held the spring pressed down by tying knots all around, then inserted the spring. Then fixed the large washer, the small white washer and then the black locking washer. Then used a sharp thin surgical blade to cut the thread and pulled it out to release the spring.
Well, with all these extraordinary works on this antique walkman, I fixed the PCB back and started re-soldering the motor, speaker, head and mike connections. I noticed that the red wire of the mike had come out. So, I had to dismantle the mike and fix new red and black wires, as these were so flimsy that it just snapped. The set was finally found working very well on repeated trial, to my relief for the toiling work done on this wonderful set of Sony:
Mission accomplished and a very great satisfaction got added to its collection.
Special notes: (1) Use innovative ways to solve a problem such as in this case, putting the washers back on top of a strong spring that was difficult to hold in place. (2) Its laziness that forces us to return the set unrepaired when we find parts are broken. With a little bit of efforts we can set right many such cases. (3) Body is always ready to do what we want; it is the mind that says ‘don’t, don’t’. Mind says so, because of our enjoyment of laziness in the past and giving a wrong input to it.
Learn to persuade it to accept what we want to do, to succeed in our efforts and missions. (4) Every such out of the box thinking and implementation will fill up our tank to propel forward.
In this case, why the customer brought the set knowingly that some parts are broken? It is his confidence that I will try my best to set it right. It is like we approach a doctor with umpteen number of problems, who face it coolly with confidence and set right.
This article was prepared for you by Parasuraman Subramanian from India. He is 72 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
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S K VERMA
March 3, 2022 at 8:44 pm
Really it is a great article for the people involved in electronics like me.
keep it up.
Parasuraman S
March 4, 2022 at 9:41 am
Many thanks!
Akhil
February 15, 2023 at 1:45 pm
Same stem of push button and spring was broken when i bought from repair shop day before yesterday, i was wondering what part it is of. also mic connections are detached as wires are very flimsy. Lets see still looking for it's rubber belt. Don't where i can get one in India.
Akhil Rai
March 8, 2023 at 1:36 am
I have received my belt from Mana_Tree (https://www.ebay.com/itm/323959197837) seller on ebay they are the best. Quality is superb, packaging and labling are also superb. Have changed new replacement belt, fixed forward push release stem with spring (I have super glued it and then put a layer of baking soda around the stem carefully than again dropped super glue), fixed mic connection with my old apple earphone wires. Now it plays,farwards,rewinds and does recording. Haven't caliber motor speed as seems fine or maybe a little slower if I have to point it, will look for those 3000k cassette.
ANIL KUMAR V K
March 3, 2022 at 9:12 pm
Great sir
Parasuraman S
March 4, 2022 at 9:42 am
Many thanks!
Albert van Bemmelen
March 3, 2022 at 9:44 pm
It is not exactly clear what was fixed and how it was broken but no doubt a great task you successfully managed to pull off (or on? lol)! I never used Fevibond myself before but noticed that you used both superglue and added fevibond to it?
Parasuraman S
March 4, 2022 at 9:48 am
The centre plastic pin on which the spring that pushes the press buttons back to its place, was found broken from its stem. That is what I restored. Secondly, there is a spring that holds two levers together, which get engaged while pressing FF or REW. That holding part was also broken and I fixed it. Well, unless one has an experience of opening and fixing tape recorder mechanisms, it will be difficult to follow however illustrious the explanation could be.
Yes, I use Fevibond first and add superglue on it when it just dries so that it become a strong bond like Araldite. This is a trick taught by my techie friend.
Many thanks for your comments and observations!
Anil
November 30, 2024 at 10:45 pm
Sir, I have fixed that plastic pin,which holds spring, but, new problem occurs, play,rew,ff,buttons don't holds, may some fevi quick or araldite interfere the place, I am unable to restore the holding of switches
Erik
March 3, 2022 at 11:39 pm
a doctor with yen number of????
yen is the value of Japan!!!
i suppose ten number of
ok
erik b.
NL
Parasuraman S
March 4, 2022 at 3:56 pm
I meant 'with umpteen number of problems' Many thanks for pointing it out.
Yogesh Panchal
March 4, 2022 at 4:13 pm
Sir,
Good attempt!
Innovative Ideas with available resources will boost confidence to tackle the problem.
Parasuraman S
March 5, 2022 at 7:08 am
Many thanks!
Waleed Rishmawi
March 4, 2022 at 6:59 pm
I am so bad with mechanical loose parts and do not bother to put them back or even look at them so I know what you had to go through to get up and running. thanks for sharing and have a blessed day
Parasuraman S
March 5, 2022 at 7:08 am
Many thanks, dear friend!
Anil
November 30, 2024 at 10:48 pm
Needs belt