TU-717 owners question

[jerrycpor]

I just completed a upgrade and modification on this great unit, and have a question, hopefully from somebody who can check their unit and report back.

When I switch between any of the Auto, Mono or AM buttons, this tuner takes a couple/few seconds for the sound to come back, it is silent at first, with the sound slowly coming back, kind of like a tube unit warming up.

Is this normal, or does your unit switch with sound immediately coming out? I don't recall how this unit reacted prior to upgrading unfortunately.

Thanks in advance!
Jerry

 

[Pepa]

Is this normal, or does your unit switch with sound immediately coming out?

Thanks in advance!
Jerry

No,sound comes right away

 

[Hyperion]

I just completed a upgrade and modification on this great unit

What was the modification you made? - what components did it affect?

 

[jerrycpor]

Thanks Pepa. That is what I thought it should be doing. Looks like I have some sort of issue with the F-2680 board then...time to go back in.

Hyperion, I performed the performance modifications per Jim and Bob's DIY mods on fmtunerinfo.com. I actually replaced most all of the electrolytics in the unit, and the vd1212 diodes as well. It sounds very good, but think I need to solve the fade in condition, before I send it to Punker X for an alignment.

 

[Hyperion]

Are you sure you got the right value for C25 on the F-2680 board ?

You didn't transpose C24 & C25 by any chance ?

 

[jerrycpor]

Funny Hyperion, you nailed it, well partly, I didn't transpose the two, just had a wrong value in there.

So I just got it put back together after replacing C25. The tuner site says to replace the original 6.8uf with a 10uf 25v, I must have had a wrong value in the bin or blurred vision at the time. The cap installed was a 100uf 25v.

Now it's headed off for an alignment.

Thanks!
Jerry