Yamaha T85

[coredump]

Hi
Any body here has suggestions to improve this Tuner? Thanks
http://www.fmtunerinfo.com/yamaha.html

[Russ-PA]

Best thing you can do is substitute narrower IF filters for what's in it -- presuming that a) what's in it is what it came with, and b) there's nothing really wrong with it. There are at least a couple of members who have done this and a couple of others who have filters available. IIRC the T-85 has 5 IF filters, and the exact complement would depend on whether you're in a strong signal area or not and how much audio clipping you might be willing to accept as a result of going past a certain number of very narrow filters.

[coredump]

on T85:
those IF filters that you are referring to are capacitors right? what does these things do? to create a better bandpass or notch filter? will it improve reception.

On Reception:
On certain channel, the reception is clear and distortion free, while other channel tends to distort and mute when signal is weak. what is the judgement on the reception at my place (highrise building). only 4 out of 10 channels are listenable.

I read some notes that mentioned passing vehicle radio causing crackling noise (ignition sound), any way to combat this?

with better antenna:
considering getting myself a magnum dynalab ST2 antenna for better reception.

I am trying to sought out all difficulties before investing in a good reception tuner. hope you guys can help me iron out all the reception issue too.

Thanks in advance.

[Russ-PA]

No, they are not capacitors, although they may physically resemble them. They are filters which narrow the width of the received signal and reduce interference to/from adjacent channels. Essentially the bandpass is reduced.

In a high rise, a good antenna is a must, and your symptoms indicate you don't have that. I'm not familiar with the one you mention, though. High rises are always a problem for reception.

As for ignition noise, unless you're located on floor one or two or within two floors of an indoor garage, you shouldn't have that.

[bnollman]

1. Are you using some kind of antenna (rabitt ears would be better than nothing next to a window).

2. If this tuner has been modified by any number of people the unit will mute and cut in and out on certain freqs if you don't hit the "fine tuning" button after changing frequencies. So try that on one of the bad channels - tune to say 106.7 and then hit the fine tuning up or down button so the display now shows 106.70. Any better ? If so, the CSL has been disabled (I prefer it that way for better stereo and sound on weak signals - defeats the built in muting)

[coredump]

1. Are you using some kind of antenna (rabitt ears would be better than nothing next to a window).

2. If this tuner has been modified by any number of people the unit will mute and cut in and out on certain freqs if you don't hit the "fine tuning" button after changing frequencies. So try that on one of the bad channels - tune to say 106.7 and then hit the fine tuning up or down button so the display now shows 106.70. Any better ? If so, the CSL has been disabled (I prefer it that way for better stereo and sound on weak signals - defeats the built in muting)

Hi. rushed to get myself a Magnum Dynalab ST2 antenna (vertical omnidirectional 1/2 wave Fm antenna).. actually don't what that description meant?

mounted the antenna indoor & close to the window. reception was just slightly better. one of the channel on classical has slightly better reception. It was when i opened up the window that the reception gets better on other channel. going to trial & error at a few more spots.

1. will having a adaptor degrade the signal?
2. does shortening the cable helps?
3. did the new antenna helps?

back to the tuner T85:

yes, yes, the irritating cut-in & cut-out. I chose to give that channel a miss.

so if i assume the unit has been modified, i need to fine tune it, did i get what u suppose to mean?

i don't get you on the CSL part. i need to put it to 2 decimal places and if i get good reception. CSL is thus disabled? should i open up the casing instead?

Thanks :duh:

[coredump]

No, they are not capacitors, although they may physically resemble them. They are filters which narrow the width of the received signal and reduce interference to/from adjacent channels. Essentially the bandpass is reduced.

In a high rise, a good antenna is a must, and your symptoms indicate you don't have that. I'm not familiar with the one you mention, though. High rises are always a problem for reception.

As for ignition noise, unless you're located on floor one or two or within two floors of an indoor garage, you shouldn't have that.

yes, i have been avoiding FM for a long time due to poor reception. however, i decided to give FM another try for the luxury of non-stop music all day and night.

if things don't go well, then i will go for the DAB tuner.
:)

[bnollman]

Can you post a digital picture of the PC board inside ? The front half of the board is what I'd like to see.

[coredump]

Can you post a digital picture of the PC board inside ? The front half of the board is what I'd like to see.

tried opening up the top cover, but failed. couldn't figure out how to remove the top lid after removing 4 screws.. :(

one of the channel got almost full FM strenght :)

[rseaman]

I have a T-85 which probably does not have filter modifications and the CSL circuit will cause strong local stations which have multipath signals to be muted. This will make the signal appear as if it is completely gone as you are listening. The signal strength on the signal meter drops to zero also. By using the fine tuning to go from 107.3 to 107.30 (a sample frequency), the CSL (Computer Servo Lock) is defeated and you receive the signal without the muting. The Magnum Dynalab ST-2 antenna is a whip antenna which is cut to 1/2 wavelength probably for the center of the FM band (98 Mhz) which can be placed horizontal or vertical. You can probably do better with a pair of VHF TV "rabbit ears". They are available from Channel Master and other sources or possibly they still carry them at Radio Shack. Get a basic set of VHF TV "rabbit ears". Stay away from those with selector switches, they only detract from the signal pick-up of the antenna ("rabbit ears"). They are much cheaper than the ST-2 and most likely will work better. The "rabbit ears" are a dipole and the ST-2 is a monopole. I have been using the VHF TV "rabbit ears" for many years in indoor applications where an outdoor antenna is not practical: dorm room, apartment, office, etc. I have always had good results with the VHF "rabbit ears" for FM reception. The closer you are to a window which faces the direction that you want to receive signals from, the better the reception will be, especially if there are a lot of steel beams or reinforcements in your high rise apartment building. I currently am using "rabbit ears" with the T-85 in my office with very good results.