Electronics > RF, Microwave, Ham Radio

Restoration of FT-480R

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Today I've found on the dumpster an FT-480R missing some front panel parts.
When I got home plug it and the radio is put in RX mode, but (there is always a but) no display.
With one portable radio I press the PTT and track the signal with the FT-480R, all was good on RX, click the PTT of the FT-480R and the radio is TXing.
First job will be replace all the electrolytic caps, the see what is going wrong with the display.
Will upload the manual and pictures.


I had an FT-480R many years back, I do not even remember when  ::) Anyhow, I also had trouble with the display which I fixed. Think it was a cold solder joint or the DC/DC converter which feeds the display with a minus-voltage-something. Could have mixed up that with the IC-211E because that one was really full of cold solder joints.

Radio Tech:
Nice find  :-+
All mode VHF is rare as hens teeth.

Well on the second time that I turn it on, the display came alive  :clap:, but not for long the digits start to disappear on after the other, and then no dispay  :-//.

The sirvice manual is here < http://www.radiomanual.info/schemi/FT480R_serv.pdf >, will upload some photos tomorrow.

The display is on page 190 and 191 of the PDF.

That show the 7805 (Q28) feeding the 16x 2SA733 (Q03 - Q18), also shows the signal leaving the UPD 1511-011 (Q01), also +13V from T01 after Q30 that feed the display, the middle of the display show -24V that comes back to the T01 (DC-DC converter).

Will have to check all this.

I hope that this is better not be display LD8231/F1P9C5, that is rare, they use to be install in some calculators in the 80's.

I will have a look att the schematic, and yes, I remember now that it was the -24 volts I hade problem with.



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