Hi, I've just picked up an old Hitachi trk-5854e portable radio cassette player from a junk shop, it works well on FM and picks up stations clearly but it won't pick up radio 2 which is on the extreme left hand side of the dial. I have taken it apart hoping that I could alter the string that goes round the tuning capacitor but it seems the tuning capacitor is going right to the end of it's rotation so I,m not sure why it won't tune down to radio 2. Do I need to replace the variable tuning capacitor or can I adjust the screws on the capacitor somehow to get it to tune down to radio 2?
Yes the radio should go down to 87.5 and radio 2 is 89.1
The sound quality on FM is very good for a portable but as I only listen to radio 2 it would be nice if I could sort the problem out.
I,m sure it's not the aerial as it can pick up all the other stations very clearly and have never had trouble picking up radio 2 on any other radio before, it just won't tune low enough to reach radio 2.
indeed, don't alter anything.
The RF amplifiers, frequency converters and bandpass filters are very complex. One small adjustment is likely to ruin performance.
Even with time to think and I can't really come up with much.
Once you start altering the tuned circuits then you will never be able to bring it back to correct alignment without doing a full re-align which means having the necessary test gear.
Is the dial calibration out around the mid point on the scale ?
At the very most you would be looking to alter the local oscillator which does often have a couple of adjustments, one for the top end of the band and one for the lower.
The question of why the problem exists in the first place should be considered. Has the radio possible already been twiddled ?
What you mustn't do is alter any of the IF strip (intermediate frequency) coils.
Once you start altering the tuned circuits then you will never be able to bring it back to correct alignment without doing a full re-align which means having the necessary test gear.
Is the dial calibration out around the mid point on the scale ?
At the very most you would be looking to alter the local oscillator which does often have a couple of adjustments, one for the top end of the band and one for the lower.
The question of why the problem exists in the first place should be considered. Has the radio possible already been twiddled ?
What you mustn't do is alter any of the IF strip (intermediate frequency) coils.
I can even get classic FM on this junk shop Hitachi which is a very weak station coming from another transmitter which is miles away.
I think I,m getting out of my depth already, where do I find the local oscillator? Maybe I should just take it back to the shop, I have seen the same model on eBay, perhaps I will have more luck with that one.
You would need the service manual. Typically the adjustment would be one (but which one ?) of the small trimmer caps located within the main tuning cap together with perhaps a coil to adjust for the lower end of the band. That could be a fixed coil consisting of just a few turns of wire, the tuning being accomplished by bending the wire to alter the coupling between turns.
If you have only paid a couple of quid then it might be worth the risk of having a play but otherwise RF alignment is a specialised job. And as mentioned earlier... why is it out of whack in the first place ?
If you have only paid a couple of quid then it might be worth the risk of having a play but otherwise RF alignment is a specialised job. And as mentioned earlier... why is it out of whack in the first place ?
Radio 4 should be at 103.8 and it is around 104 on the Hitachi and radio 3 is roughly at 92.5 on the Hitachi and should be at 91.3 which is I guess not too far out. So maybe the dial is going low enough for radio 2 but there's not even a hint of it which is strange because the rest of the stations are fine. If this is not a simple fix I think I will just take it back.
Maybe it's a Welsh radio telling me I should be listening to Radio Cymru not radio 2
I would have to say no (unless you are prepared to risk totally screwing it up). You have to ask yourself why it appears out of alignment. Something has happened, either there is a hidden fault or its been twiddled already. On something of that age its quite possible to find a problem with those small compressed disc ceramic capacitors... they can and do fail typically going a little bit leaky.
Its either leave it as is or carefully experiment and treat it as a learning exercise.
Its either leave it as is or carefully experiment and treat it as a learning exercise.
OK thanks, if it's not a simple fix I will take it back to the shop. Regarding capacitors I did not know that ceramic ones could leak I thought only electrolytic could leak?
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