sx 1080 tuner

well ive decided i cant live with my fm tuner any more as it sounds terrible. records and tapes are no problem.do to my location and inability to find a competent alinement tech forces me to ask 3 questions, if i can find a tuner board can it be recapped and alined outside the receiver if so are any techs available to do it? if i recap the tuner what can i expect to happen with no alinement equipment?

well no one has responded to this so ill tell you what happened. theres probably not too many folks in my situation,living in a 3rd world country trying to repair ancient stereo gear with no adult supervision save audio karma and specifically mark the fixer and those sainted individual's who have posted capacitor and transistor replacement lists. im forever in your debt! as for the 1080 tuner it was becoming really irritating to listen to. i had the capacitors for the tuner and not much to lose so i had a go as the aussies say. i started changing all the blue nichicon caps one at a time.each time i powered up the set and listened to the same fm broadcast nothing seemed to change until i got to those tiny egg shaped buggers and the world changed for the better when they were gone, but there were TWO in particular that dramatically improved performance. it is now actually NICE to listen to! i can only speculate how much better it would be if it was properly adjusted as per service manual! it even tunes in on scale! unless there's some ticking time bomb ive set in motion i wouldnt hesitate to do this again if the need presented itself. as far as the stereo signal lite it and the fm on light are concened they are burned out. the tuning meter is still offset about 3/8'' of an inch to the left of center at good reception. this was approximately 6 volts at the meter. maybe ill meet someone eventually who can aline it properly. i was tempted to adjust t6 but decided not to tempt fate. do any of you know where i can get an led conversion for the illumination AND indicator lights????

I have done the same here in the States. FM sounds like Dog. I replace all the caps on the tuner. Most cases its a dramatic improvement and nothing else is needed. I have a pro near by if I need an alignment. Lucky! If you can tune to a strong station and get the channel meter to center with good separation you can move the pointer to match the dial. First check and make sure the pointer stops at both ends of the dial. Some one could of moved it before you.

Ok, how does the signal strength behave? A strong station puts the needle towards the right?

The centering of the tuning meter is set by tuning to dead air (can't have a weak station pulling at it or it will be off) and adjusting one of the t6 slugs (as per the manual, step 8). Put a direct short on ALL the antenna inputs for the FM centering set.

Tell me which cap numbers as per the schematic made the most difference and I'll do some head scratching. There are about 11 tantalum caps in there. The two I can think of are c39 and c40 in the stereo decoder. C39 says 1uf on scat, and 10uf in list. Scat is correct. 1080 parts list is wrong. Cross check with the 980 and 1280 tuners on that chip and their caps that are connected to those particular pins.

your stereo light may not be burned out, but rather in need of adjustment (vr5) split the mechanical difference of the lamp off to lamp on transition point of cw rotation and the lamp off to lamp on transition point of the ccw rotation. NEVER use the lamp ON to lamp OFF transition.

I wasn't in AK much to follow things. Sorry, but other things intervened, and this fell behind because it was never bumped to the forefront, and thus fell through the cracks.



Lastly the best you can do is to try to dial in the distortion by ear with the second t6 slug. Classical music (piano, violin) is better than rock or pop for this.

im sorry i didnt make note of EXACTLY which cap's by number made the difference. i thought i was on my own.my bust.i did find a deviation in the list but paid it no mind as i replaced each cap by its VALUE to the removed part. using the list to show me the TYPE of cap. YOU TAUGHT ME THIS as there can be differences in these boards even with the same part number. but it was one of those little blue buggers.as to t6 i looked down the center with a mag lite and couldn't see the drive. their wording was deceptive in that it suggested there was more than ONE adjuster on t6 and i didnt want to spoil my success. exactly WHERE IS AND WHAT type of tool to adjust this for the tuning meter? both the stereo and fm lites are burned out looking for led's . will shelve the lite adjustment until the cavalry arrives. the signal strength meter is centered off, when the unit is powered on the needle swings to the left abut 3/8's of an inch and STAYS there until it finds a station. its movement is then a deviation of about 1/4'' from this off center position,using the tuning knob

t6 has two internal independent cores and needs an undercut plastic hex (like an allen wrench) adjusting tool to turn one without bothering the other...

That means the tool is a smaller hex shaft that at the last 1/4 to 1/2 inch gets a bit larger.

(I'm (edit STILL) LOOKING for it)

In reference to the earlier issue, bump the thread up. every couple of days. When it falls back, and drops through the cracks, it is natural to assume that the OP has lost interest, gone elsewhere or something like that. I have so much going on, and things popping in and out, that I just start at the most current posts in threads that I have already posted in and work my way backwards as time permits. Somebody else might have answered those bumped posts...

And IF I get cranky about bumped posts, point me back to this where I tell myself >>> YOU ASKED FOR IT BUB <<<<

Good used tuners are quite cheap.

If I were you I'd pick up one and run it thru the tape monitor input.

You could pick up something like a MCS 3700 or 3710 for under $50.

gotchya what size in mm's is it. have steel wrenches and bench grinder and can make tool. can power off the set tweek one way or another and power back on to check effect. inefficient but doable. as for slow jazz, thanks i got one,its how i made sure it was the tuner. looking on ebay for awe 092 but no joy yet. and then id still have to find someone to recap it and aline it OUTSIDE the set if thats possible

It MUST be PLASTIC!!!! Not metal.

And I haven't yet found the dimensions, or a part number or a link.

It is expected that the unit is ON when those adjustments are made on T6.

Problem with all these old tuners is, things eventually wear out (mostly ecaps) and need replacing.
As far as changing ecaps in tuners, there are no ecaps in a 1080 that would affect the alignment, if there are, which ones are they?
All of them are used for either DC supply filtering or signal coupling. Not even the ecaps in the stereo PLL decoder affect its VCO adj.
One problem is having to take the dial string apart, to get the pcb out, if you do not do it the right way, then you are toast and usually mess things up.
Adjust the FM detector is a critical adjustment and to do it correctly you really need a THD or FFT analyzer and a good RF SG or you are just guessing.
Lots of old TV alignment tool kits available still
http://www.ebay.com/sch/i.html?_fro...XTV+alignment&_nkw=tv+alignment+tool&_sacat=0

thanks rcs16 i dont know beans about radio except the crystal radio's i fooled with as a kid. looking for the special tool mark was referring to, to adjust the tuning meter signal to center it.this is the special allen wrench that adjusts the lower slug only. i dont know what size this thing is and im not sure where to locate it here in the philippines. ive looked at your link,and some sure look incriminating but which one works for sure? mark seemed to think it was a hex.this suggests an allen wrench are there any other types square for example? i cant see down the hole with a flash light to see what it is.i was warned against metal tools,even powered off. do you know what i need?

Mark KNOWS EXACTLY what it is. He has/had to dig it all out.

A plastic alignment tool.

The tool CANNOT be metal because of physical properties. Metal detunes the core you are trying to adjust, throwing everything off. This MUST be done with power on and the unit operating.
It has nothing to do with electrical shock.

Also metal hex wrenches could crack a reluctant core, then you are up the polluted creek without a paddle.

I stopped specially to grab my tools and a micrometer, to get these measurements and identify the tool. THEN I had to dig out a awe-092 tuner board (only partially stuffed) and check the T6 ate-030 fm detector transformer slugs and their size.
It is ~0.075" (5/64) on the flats. The undercut shaft is a round at 0.065" diameter.

Download this catalog fragment http://www.gcelectronics.com/order/SubCatPDF/alignment tools Kits 380-387.pdf

First page, AS-9300 figure 7.

I actually stuffed my 9300 tool into the T6 ATE-030 transformer and turned the ferrite slug.

I don't know if this will be that helpful, but I saw this post on the Antique Radio "Hints and Kinks" forum, one guy was able to use a FM stereo wireless headphone transmitter to help in an FM Stereo alignment, in place of an expensive stereo signal generator.

http://antiqueradios.com/forums/viewtopic.php?f=10&t=257554

What do you guys think about this?

John Stumpf, Have you seen the Tuner Cleaning tutorial in the Tuners forum? It works wonders on some tuners:
http://www.audiokarma.org/forums/showthread.php?t=144163

If you can control the RF level then it might be useful. You need a RF SG to be able to peak the coils and trim the var caps at either end of the scale.
Like Mark is asking, need to figure out what it is and not doing then we can figure out a coarse of act.

John,
Do the quad null test, short one of the FM inputs, 300 ohm or 75 ohm, then tune to a place on the dial that only picks up noise, is the center-tune meter centered? If not, you have to adjust primary core of T6, bottom core for center or as close to 0 volts across R26(510ohm). Not sure if you can access the bottom slug underneath or you have to place the tuning tool in the top, engage the top slug then let the tool go down to the bottom slug and have to turn slightly back and forth so that the tool engages the bottom slug, ( remember or mark how much you had to move the top slug, center the meter using the engaged bottom slug, then lift the tool back up to dis-engaging the bottom slug, and then put the top slug back into the position where it was originally. Now you are supposed to adjust the top slug for minimum thd, and then go back to the being as the two slug interact a bit. You can try Marks method but I cna not say I have ever done it that way, only used instruments. Just keep track of where the top slug was originally, phew make sense guys?

all this gets shelved for a couple of months till as9300 gets here. ive book marked this.as far as the tuner goes i cleaned everything with a vacuum, brushes and ethyl alcohol when i did the recap. brushed lint out of the variable cap and deoxited the brass shaft wipers. i will review your link to se what i missed. once again thank you all.

well the tools arrived and i had at it. to those who attempt this, my suggestion is using the heavier body wrench and go from the bottom as mine was to stiff to turn from the top with the reduced thickness tool that allows adjustment through the top slug. BUT it was no cigar as the the best 0 volt dc i could get was .069 vdc. it still yields a left deflection of about 3/16 of an inch. the bulb is definately burned out as the stereo light has 4vac applied to it. unless some one has more ideas i guess it stays that way. thanks again to you all.

Shouldn't be AC to the stereo lamp. 13v on one side, 160 ohms to the chip (and then to ground when on) on the other, DO NOT short pin 6 of the chip or pin 15 of the board to ground to test the lamp - 8v lamp at 13v will hurt (pin 15) , as well as shorting pin 6 of the pa1001 chip to ground to light the lamp. IF you have to test the stereo lamp, use at least 220 ohms to ground from pin 15.

was 0.069v with NO signal tuned, with either dead air ,or in a crowded market, the antenna input shorted for QUIET dead air.

My 1080 tuner is slated soon...it gets "staticy" after it runs for a little while, never recapped it during the main recap

well i pondered your reply mark, and rechecked everything today. i got the following results. power supply 16 is 13.36 vdc to ground. moving the ground probe to tuner 15 and there is 2.179 VAC freq. meter reads 60.02 hz!!! using the dc scale it is a jumpy .019 - .024 vdc it never goes to zero or much higher tuning stations. after playing with t5 yesterday, i put it back in its original setting. for the hell of it i turned the set off. placed meter probes on tuner 16 and ground pin 16 reads 4.05 vac at 60 hz. the set is turned off mind you. i UNPLUG IT it naturally drops to zero. turn the plug 180 degrees and reinstall in the outlet and i get 105 mvac at 60 hz. i have no logical explanation as to why the results are so different from yesterday or how the tuner can be a source of ac voltage. it still works mind you

i have just found a maintenance error. it appears that i installed c26 or it could be c28 cant tell for sure due to poor quality schematic, reverse polarity. this cap is directly inboard from pin 28.what have i done !!!!??? i have replaced the cap and it still behaves the same and fortunately still plays