Denon Tuner Problems - Please help

[rwaters2]

Hello everyone,
Can anyone help please - I have a Denon receiver (tuner/amp) which has a problem whereby the FM radio frequency readout is out of sink.
For example, if I tune to Radio 2 (89.10) I can only listen in stereo at 89.15, also if tune to a local radio station which should be 102.60, this only plays in stereo at 102.65 - This fault applies to all radio stations - they all tune in 0.05 above their stated frequency.
Are there any adjustments that can be made to make this tuner "normal" again ?

Thank you.

[Bobken]

Hi,

Regrettably, it seems that this tuner is in need of re-alignment, but this will require quite sophisticated test gear to enable this to be done properly, and it is not something which an amateur can readily improve.

If you cannot live with this as it is, I would entrust it to a suitably-experienced technician as re-aligning tuners is not something which even many audio engineers are capable of making a good job of, in my experience.

Regards,

[anatech]

Hi rwaters2,
It sounds like the discriminator coil is out of adjustment. Any good audio service shop should be able to handle this at low cost. I would ballpark this at an hour or less labour off the top of my head.

-Chris

[Bobken]

Hi,

Well although he appears to be in Canada, it seems that Chris is more familiar than I am with what to expect from UK servicing personnel, which is perhaps because my experience in this respect is 'limited' to merely 40+ years.

The fact remains that although this is not a long job to undertake, if one area has drifted out of alignment it is likely that the unit will benefit from a more thorough check-over, especially while this unit is opened-up on the bench, but this will partly depend on how long it has been in use, of course.

Irrespective of this, most service centres in my area will not carry out tuner alignments, anyway, I suspect because they probably don't have an RF Sig. Generator, and one company has even asked if they could borrow mine in the past!

Being similarly practical but of more significance, unfortunately with those who will undertake this kind of work, they have minimum charges in excess of £50 (including VAT) to even look at such a job, and I simply question if it is worthwhile accepting this level of outlay merely to correct this apparent minor display anomaly.

One thing I am sure about is that unless you know what you are doing (and, with respect, I guess this will not be the case as you needed to ask this question) you are not likely to achieve any benefits through any internal adjustments you might try yourself, especially if you don't have a non-metallic trimming tool to use.

I would suggest that you initially make some local enquiries, or perhaps with the Denon Service Centre in the UK, but do take care over whom you give this job to do, assuming you decide that it is worth it.

Regards,

[Mooly]

Hi, Is this a "true synthezised digital tuner" or is it an analogue tuner with a digital display. I ask because I still have an old Sony STR515L, an analogue model that has both the traditional tuning scale and a digital readout of the tuned frequency. Could it be problem with the display part only ( Really just a frequency counter ) is there a trimmer cap to tweak the master oscillator of the counter ? If as Chris says the discriminator needs a tweak, I fear you will have problems. As Bobken hints at, certainly all the service depts I have worked in, ( and they were for major companies ) would not undertake this kind of repair. Very sad I know, but thats how it is here. Now very unprofessional this, but with the tuner opened up and working try gently inserting a metallic trimming tool into the suspect coil. Don't adjust anything, just see if it alters/cures the problem. Now I did'nt just say that.
Good luck Karl

[rwaters2]

Just wanted to say a big thank you to everyone that's responded to my query.
I have received a quote to have the Tuner section "re-aligned" and have decided to put up with it for now - The quote came in at a minimum of £50, depending on the involvement of the actual repair.

Best regards.

[Bobken]

Hi,

No need for any thanks, and I am sorry to hear the outcome of this, but it is just as I suggested, regrettably.

Often these bills get 'inflated' in my experience when it comes to paying them, and you are over a barrel at that stage.

It is lot to fork out for something like this, anyway, and for now I believe that you have done the most sensible thing. So long as you don't have any further problems I guess that it is 'liveable-with', and if anything else goes wrong, you can always reconsider the matter at that time.

I hope that you don't have any other problems, though.

Regards,

[anatech]

Hi Bob,
I do a fair amount of tuner work. I do have the required equipment and more. To me, the job does not look that complicated and I was authorized warranty for Denon for many years.

Hi rwaters2,
Bob was correct in that you have to be careful where you take your unit for service. This applies for all service and it is indeed a sad state of affairs. In my view, £50 should cover the service without any trouble. These are not complicated and there are not that many adjustments to make. I an see where the shop is trying to cover their bases as it's not possible to guarantee a service cost until the job is actually done. The odd sneaky problem can show up. I strongly doubt there are any other things out of alignment in your tuner. For example, the IF strip is fixed with ceramic resonators. It is not possible to adjust them and they are very reliable. The frequency displayed is read directly from the local oscillator of the front end and the IF frequency is subtracted (or added as the case may be). This is your tuned frequency. It is defined in logic. The only thing that can cause your problem is that the discriminator is off a bit which throws the 0 VDC point out (how the tuner figures out where the station is exactly). This will greatly affect the distortion level as well (there are two adjustments, one is for distortion). So your tuner should sound much better once aligned.

Did this happen suddenly, or was it a gradual thing?

-Chris