Resurrecting NATIONAL Two-In-One Model RX-FT500
This National Panasonic 2-in-one was brought to me from a faraway place by a regular customer, requesting that it be restored to the best possible condition, because of the double cassette playing and synchronized play; i.e. the second cassette would automatically start playing, once the first one is over. This belonged to the tape recorder era and was once a fancied set. A similar set can be seen here:
https://www.radiomuseum.org/r/panasonic_stereo_radio_cassette_recorder_rx_ft500.html
Coming back to our set, let us have a look at the inside of this neglected set:
It took hours before I could complete cleaning of every part, after dismantling it.
I replaced all the electrolytic capacitors on the two boards.
Also retouched the boards with fresh solder, without leaving any point.
Cleaned and lubricated all switches and controls. Replaced the belts, which were in pieces. There were catches inside the wheels. So, I had to dismantle the mechanism and clean and lubricate every part; the play wheels, gear wheels, capstan wheels, some levers etc. After spraying the mechanism with CRC 2-26, pressed and released all switches on the mechanism several times to free them.
Then applied power externally to the motor and checked the functioning of the mechanism. It was working very well. Then connected the boards externally and applied power to check the audio output from the mechanism. It was working very well and even the synchronization was functioning well. Then turned my attention to the radio. The radio was not working at all, in spite of the fact that all caps were changed and retouched the solder points. The voltages at the pins of a couple of ICs were not ok. So, replaced the ICs, upon which the Radio started working very well, except the FM. I even replaced the Crystal and ICs too. But it was working on some frequencies not covered by FM Radio broadcast. After several futile attempts, I contacted the customer and he told me that it was being used for receiving satellite Radio and that could be the problem.
Though the specifications or markings printed on the dial showed the normal FM band range, this Radio seemed to have got tuned to some outside ranges, perhaps due to defective oscillator coil or the Gang itself. Anyhow, I left it at that. Rest of the functions were working very well in the set and I called it a day and fit everything back as it was and kept it ready for pick up by the customer. Mission accomplished to the best of my ability and satisfaction did not find any reason not to get collected.
This article was prepared for you by Parasuraman Subramanian from India. He is 74 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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Waleed Rishmawi
December 9, 2023 at 2:41 pm
the coils could be rusting inside and there is nothing can be done about that but you did an amazing job there. have a blessed day
Parasuraman S
December 9, 2023 at 10:46 pm
Many thanks dear for your continued encouraging comments! You are right, coils could have got rusted inside.
Albert van Bemmelen
December 9, 2023 at 3:29 pm
This article was another good example of a very time consuming repair on a device that normally needed a lot of hands before it was assembled and ready for shipment.
Parasuraman S
December 9, 2023 at 10:47 pm
Many thanks, dear, for your comments and encouragement!
Yogesh Panchal
December 12, 2023 at 12:23 am
Radio Reception tuning setting is really headache for me,because now a days many Magnetic & electrical interference is surrounded in house like LED Light & so on.
Repairing Involved mechanical as well electronic is really enjoyable work.
Parasuraman S
December 12, 2023 at 11:34 am
Yes, very true. Radio does not work properly in my service room. But it works perfectly well in my sit out. Everytime I have to switch off all disturbing electronic devices, including my soldering iron station and computer before I can get proper signals. Many thanks for your comments!
Dr Ganga Phd music
July 17, 2024 at 11:40 am
Happy to learn about yr skills sir. I need to repair my national two in one one cassettes play button is not fixing in place pops out. Hv many old cassettes of music lessons indeed to archive pl help advise.