Another 550T saved.

larryderouin

I'm VERTICAL and Breathing...most of the time.
Subscriber
Got from a retired Gentleman in Springfield Va. Cosmetically a solid 8.5. Couple of marks on the FISHER WOOD CASE. The Metal Screen is intact and not bent. The AM Antenna may need to be rebuilt as it feels as if the ferrite bar is broken internally. All knob brights are there, and the lettering is a 9.5.

He bought it new in 1968.
Mechanically it works in all modes. The switch gear needs a solid De-Oxit Bath as the FM is intermittent with actuation of the switches. The AM is LOUD AND CLEAR! Sounds very good, rich bass, mids are nice and crisp, and the highs have just a bit of a bite to them. Loudness, Low and High switches plus the FM Mute need Deoxit bad. Phono is good, as is Aux. Tape head jacks have shorting plugs in them.


He had an absolutely gorgeous DUAL 1019 also. Too bad I couldn't meet his price. Original base, cover, short and long spindle, 45 adapter, and complete headshell carrier with cartridge.

I think with a good DeOxit bath, and a tuner cleaning this one will rival or surpass my 500TX.

Pics tomorrow. I'm gonna take a hot shower and hit the hay!
 
SERIAL # 10352B (Very Early Model). The "Hidden Door" is there, but nothing behind it. Which suggests that the faceplate blank was used on multiple models.


So far I've discovered a Main Filter cap that has vented. Replacement is ordered. The other Main dual cap has been temporarliy bypassed with new Nichicons which will be stuffed internally later. They were mounted like this for testing. The coupling caps (1200 uf 55V) I'm gonna restuff also.

All switches (Rotary) were unbolted from chassis, sprayed with CRC QD Contact Cleaner and scrubbed with a toothbrush. All pots and Rocker Switches hit with QD and exercised. Some improvement in sound quality.

The FM works of a fashion. It's definately out of alignment. It acts like it's reversed in reception of a station and it overloads sometimes. I've opened up the Tuner capacitor housing, and hit it with Non Residue cleaner (CRC QD Contact Cleaner). No change.
So time for the manual and get all the cap values and start checking resistor values on all the RF/IF Boards and MPX Board BEFORE taking it in for alignment. AM/PHONO/AUX/Tapein and outs all work great.

Socketed Transistors??? Socketed (Large 7 pin sockets) Amplifier boards????? WHOA!!!! I like this almost as much as the H.H. SCOTT "Works in a Drawer" (Socketed boards that came out in 1970). I spent 2 hours last night pulling each transistor out of it's socket (after marking orientation) and cleaning each pin with an eraser and non residue cleaner. (preventive maintenance). Just have to figure out how to disassemble the amplifier boards from the chassis for cleaning and parts changing(caps, etc).

Most all of the caps are poly with the exception of the Mains/coupling and power supply caps. What lytics there are plastic housed Mallory's. Never had one of those that was bad, even tho I've replaced most all of them on the other units I have. So this one will be done in stages over a longer period. The sub 1uf caps, I'll leave alone for now as all of them are poly's (mylar, etc.)

The previous owner was a pipe smoker. The inside of the unit was/is clean, but the wood case was dry and full of Pipe smoke residue. 409 and hot water followed by Murphy's oils soap got rid of the Nicotine residue. The Faceplate was rinsed in straight water with slight hand pressure to rub. Carefull application of Brasso with a finger on the chrome edge. The Volume knob lettering is worn off almost completely. I do believe this was the only one he used as everything else looks untouched. I let the case dry in the sun, then put a thick coat of Feed and Wax on it
and let it sit overnight. Buffed off with Towel. The knobs were soaked in a bowl of Hot Water and Dishwasher detergent powder. Rinse/Dry/Brasso the caps.

Nothing done to the Front Glass, except remove the "90 Watt" sticker from the side of the case and reglue it to the glass.

Ordered a Manual from Rick @ Stereomanuals.com.

NOTE FOR JONBOY AND RED! The 550-T is the Receiver used in the 1968 Executive Model 973. Something for your notes on the Fisherconsole Site.

This one is gonna be a longterm project. But any transistor replacement promises to be easy, with the sockets(provided the new ones are compatible in size and lead out.)

Larry
All cleaned up
100_2280.jpg


As received. A little Grimy/Dirty.
100_2273.jpg


Closeup of 7 pin sockets to AMPS!!
100_2285.jpg


Larry
 
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nice

I recently scored one in the thrift store.
Filthy inside.
Completely intact including the wood case.
Cleaned it all out, a little deoxit, made some dial lamps and everything is working well.
One of my new "best-favorites"

:thmbsp:
 
Spent a couple hours on it today. Replaced the 1200uf coupling caps with Rubycons. Stuffed the dual 1000uf. Salvaged the power cord off a 175-T with a bad tuner.

The FM.....
Roof antenna hooked up.

1.) MONO FM is 1/2 way decent.
2.) MONO FM LOCAL is non existant.
3.) STEREO FM Sounds like one channel is good but the other is distorted and hollow sounding like it's echoing. MULTIPLEX?????

Defiantely in need of an alignment.

AM Absolutely no problems. Picked up a couple of stations on the Eastern shore (across the bay 80 miles or more) during the afternoon. Kinda weak but it pulled them in. Probably the best AM receiver I've heard in a long time for DX.

Stereo Beacon Lamp burned out. WJOE has the bulb.

Ordered the Main Filter cap and some others to replace all the lytics underneath.

Figured out how to remove the amp module. Kinda cool how they did this one. Pulled, cleaned and regreased the outputs. cleaned all the rotary switches to shiny metal.

Ran it up on headphones for about an hour. Transformer stayed cool to warm. Not hot at all.

case cleaned up well as did the metal grill on top. Once I get the tuner aligned it'll go up with the 500TX, in the collection. So far so good.

Larry
 
I got to thinking about the manufacturing dates and the serial. As the previous owner is elderly, I'll give him the benefit of the doubt. But I DO think 1968 is a year or two too late.

take into consideration that this unit according to all sources I've seen on the net was manufactured from 1966 to 1968, and the serial is 10352B (Fisher apparently started all their serials at 10001..) I would tend to think that this is actually a 1966 model 550-T. I have found a couple caps inside with dates of 10-65 on them. I guess 1 to 2 year old caps could be put in new gear, but I would think that the lag time between manufacture and installation of individual parts would be less than 6 months. Basing the model year from Sept to Sept would put this unit in the early 1966 model year era.

Larry
 
Got the mouser order in y'day. Manual came in Monday, and I proceeded to Mark all the IF/RF Transformers on the boards, to make it easier when aligning. Also Marked stuffed caps.


Top Picture.......
replaced the 4uf/35v cap between the 10.7 If board and the MPX board. (Swelling out the ends). Circled in GREEN

Replaced the 200uf/35V axials on the amp boards with 220uf/35V (Circled in RED)

Replaced the 1200uf/65V coupling caps with 1200uf/250V Rubycon snap in's as they fit in the clamps. (Circled Blue-Green) The bottoms look rough as my iron melted the plastic at one point in their short life in the last 6 months.
100_2305.jpg

Bottom Picture........
Stuffed the Main Filter can cap. Epoxy and Taped the seam. Need to get some new Diodes (For General Principle).

Stuffed the Dual 1Kuf can cap. Epoxy and tape the seam.

Recapped the complete power supply. All lytics Nichicon.

Every switch, pot, Rocker got De-Oxit bath, and with the Rotary's a scrubbing. All work well now.
100_2304.jpg


While doing some research on possibly replacing some transistors in the mpx, figured out that I could sub 2n2222A for the BC107B's. Replaced all 5 (love them sockets :D ) and fired it up. (Circled in Yellow Top Photo)
Set for Aux, volume @ 0 all other controls centered. Waited 15 minutes and set up the center voltage to 0volts +/- .5V. Got the Left side to +1mv and fairly stable(fluctuates +1 to +4mv) and the right to -2 and fairly stable (fluctuates between -2 and -7mv). Turned off and set up for Bias. Turned on and let sit for another 15 minutes. Both sides were 41 to 45mv. Adjusted to 40.0mv. Does not rise or fall after 30 minutes. So the amps look ok to me.

Attached an antenna to it and flipped to FM. WHOA!!!! 100% improvement in sound quality in FM STEREO. Also improvement in FM LOCAL. Still some alignment needs to be done, after recapping the small lytics. (On Order).

The Tone board is problematic. The Loudness control is barely apparent. As are the Low and High Filters. This is on headphones.
Recapping this board is on list as is replacement of the BC107B's with 2n2222A's. God knows they are cheap enough. There isn't enough lead length to test on my dmm. So shotgunning of small signal Tx's is a viable option.

It's running quite nicely right now on headphones. Haven't hooked up speakers yet. I'll get it recapped totally before hand.

Larry
 
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Well I got curious as all get out today. Hooked up my test speakers (Bose 201 Series III). HOLY SHIT!!! Except for the slight distortion in the FMSTEREO mode, this thing is absolutely GREAT! Lots of Bass, Mids are a bit subdued right now, but GOB's of High's that can get shrill. All controls are functional and proportional. Loudness, Low and High Filters work as designed. The FM Mute works of a fashion, but will come on line when I get it aligned.

Very close to the 400. It is slightly harsher than the 400 to me. But it has that 1st gen sound about it that is about as close to tube as you can get without tube in it.

Now that I have a baseline, Hurry up Mouser!!

Larry
 
Larry,

I love threads like this. We need to have a beverage together sometime and compare notes. You have a meticulous style that I admire.

Frannie
 
Thanks Frannie. As long as it's Coca-Cola for me. Can't have alcohol (with the meds I'm on). No notes, everything inside that "thick skull" that my parents swear echo's for a month! HA-HA!

I take a bit from each part that I work on and use that experience as/if it fits. It really helps that I have Previous Fisher experience, as this is about the most involved unit I've worked on(short of the 500TX). And being retired gives me lots of time to think about what's wrong, even if I don't totally understand it.

I about crapped when I saw the number of UA703E opAmps. The only place I know of to get them is NTE (I got 2 before for another FISHER and they worked well). The last time i priced them was 2 years ago. Price has come down a little. but they are still expensive to me. Hope they still run for a long time yet.

The TONE AMP is gonna be a PITA to pull out. Have to remove the AM RF board, and the DUAL 1K can to get it back far enough to clear the pots. Lots of wires to remove. Gotta make a drawing with the wire positions and colors, pictures, do the work and put it back together. Hopefully I get it right.

So far it's working fine, and getting better all the time. FM is still distorted some, but I have a local AM station I listen to that plays a lot of 60's Jazz, blues, Motown, etc. There are times I feel like a kid / young teenager while listening to this station with this receiver. I did connect a TT to it, and it did fine. Nothing spectacular but it's acceptable. AUX is a little better. I'll have to check the PEC's for the RIAA.

I end up with more work, as I dig further into it thinking about things. I just ordered the LAST of the CAN CAPS for my 400. Everything else has been done at least once on it but there is room for improvement. Just OD's and Mallory / Illinois / C-D caps in it. WAF is good (it's inside of a 61 coronet II cabinet) so I keep it in the Living Room.

Time for Bed. Revellie is 0600 and I have a full day on the Sub planned.

Later

Larry
 
Pretty much done now.

Mouser order came in today. I didn't order two 4.7uf/50V caps for the preamp, didn't realize it until I started in on it today.

SO........I recapped everything with Nichicon UPW's except the AM-RF, 10.7mHz and 455khz If boards. Replaced the BC107B's on the mpx, preamp, tone control, and main amp with 2n2222A's. New 1n5404's for the Bridge Rectifier. Filter cap's were stuffed, Coupling caps are 1200/250V Rubycon's.

Didn't touch anything on the Front End, or the IF Boards except the lytic's and the bc107's and the FM came up LOUD AND CLEAR on a $3.00 pair of Rabbit Ears. FULL BAND and all stations are where they are supposed to be. Mono and Stereo. The Stereo Beacon Lamp needs replacing (I'll get to that later).

I DO believe the problem with the FM and FM Multiplex was a couple of bad BC107b's. When I replaced them last week the FM came back but still had a few problems which went away with the recap. It probably should have an alignment done, but I don't think it's gonna be off by much. I can wait on it.


AM IS VERY STRONG with a 8 ft. piece of wire on the Ext. AM connection. The Ferrite Rod is broken about 1/2 way in. So I'll need to get a ferrite rod and slip the old one out and slip the new one on, then reseal the Wax.

No signal and Volume all the way up and I get a slight white noise. No problem as far as I'm concerned. NO HUM anywhere in any position. GOOD!

Audio problem with Loudness and Filters has disappeared with Recap and replacement of the BC107's on the Control amp. Nice and strong loudness control, and the High/Low Filters work well also.

The Wood case was extremely dry. Gave it 2 heavy coats of Feed and wax last week, and didn't wipe it off. It soaked it all up! Buffed it out today and it's still dry looking. Guess I'll have to keep feeding the Hungry bastard. :D

Larry
 
Heya Larry,

Nice progress. Dumb question. You stated that you had a full day on the sub.

Are you involved with the USS Torsk ???

Or where you/still are a submariner ?? I guess once you are you are always. Silly of me to think you are not just because you are not active duty.

Frannie
 
Been volunteering on her for 13 years now. We've got a fairly large volunteer group (about 25) that is local and then about 50 all over the country that come in once a year to work on a whole weekend. Go to www.usstorsk.org and the volunteer activities to see what we've done over the years. We just got back 2 months ago from a drydock period. Rode the boat down and back from the yard. FUN!

I got out in 1977. 4 years.

The Vol's are on the boat every Saturday. Come on down and I'll give you the Nickel tour. get there before 10am. (Even the locked areas that no one else gets to see).
The boat opens at 10 and all non visitor areas have to be locked.
Larry
 
Hooked it up in the Main system today. (Which ever receiver I choose, Pioneer PL-518 or PL-7, Teac A4010GSL, Pioneer CTF-6262, Bozak 207A's in Kanazawa Cabinets.)

Put on some Benny Goodman, Artie Shaw, Duke Ellington, Pink Floyd. Sources were cassette and LP.

Think 400 on a LOT OF STEROIDS!!!! Not so much in the Output Wattage, but 3d imaging, Stereo Separation, Depth of Field. Sound is LUSH, Mids are slightly subdued (all controls flat, loudness OFF), Bass is TIGHT except when pushed Real hard (loudness on and Bass all the way up with volume past 10:00), and Highs are laid back until I crank up the treble then they stand up and shout. I think part of it is the speakers as the controls are dialed back a little right now having been hooked to the SX-790 previously. So some tinkering is in order.

Speakers are approx 6' apart and I sit about 7' away. Close my eyes and everyone in the groups are all around you but where they should be arranged for seating. I put some Harry James on and I was standing next to him. It was freaky feeling. With the 400, I get some but not as much as the 550-T. It's(400) is kind of flat. But the 400 is in a console cabinet right now.

The controls on this unit are a little bit unusual in that the Tape Monitor is tied in with the Stereo/Mono rotary switch, and the speaker selector is located next to the Tuner dial and easily confused. Otherwise they are fine. Back side connections are typical FISHER with the speaker connections laid out horizontally by sides.

What's with the HIGH REC and LOW REC? Low and High output for recording???

Anyone know where I can get a ferrite rod? Just the Rod. I need to replace the one on the AM Antenna.

All in All I'm impressed with this FISHER. Not as much power as the 500-TX, but it's a lot fuller sound, where the 500-TX sounds flat. Once I get a replacement to fit in the Coronet cabinet the 400 will come out and I can do a A/B comparison with the 550-T. But so far the 550-T is beating the 400. It's been so long since I had the 400 hooked to the Bozak's, I think the 400 will do well once I hook up to the bozak's.

Right now as it stands ratings.....

POWER (output Wattage)
1. 500TX (65 per channel)
2. 550T (32-38 per)
3. 400 (28-32 per)

Looks
1. 400 classic, understated.
2. 550T Nice Two Tone, Not overly cluttered, WOOD Case
3. 500TX Non intuitive panel, overly cluttered with controls, small dial Face .

Ease of Operation
1.) 400. Basic Controls well laid out.
2.) 550T. Multiple use controls confusing at times to beginning owner.
3.) 500-TX Control Overload, too many Multiple use controls, FM Tuning can be confusing with the Presets, AutoScan, and Dial.

Features & Controls.
1.) 500-TX If you like the more is better catagory, the 500TX takes the cake. 3 different ways to tune FM(on the Front panel), Presets, AutoScan, Normal Tuner. Then there is the WIRED Remote (standard on the 800-T), plus the usual suspects. 2 sets of speaker connections and a center speaker tap.

2.) 550-T Think 500-TX WITHOUT the AutoScan, Presets, the Wired Remote, and about 1/2 to 2/3 the wattage. However the 550-T has a Center Speaker connection that has a OFF/ON switch next to it. Don't know if it's the usual FISHER setup(hook into another amp) or is straight to speaker. The amplifier is removable via 11 screws from the chassis. The boards, coupling caps, and the OUTPUTS are on this "subchassis" connected to the main thru TWO OCTAL SOCKETS!!! How Cool is that! Sometimes the engineers do something RIGHT!

3.) 400. What can I say about a Classic. It's the baby of it's series, but it's no slouch! Easy to work on, easy to run, sounds good on most speakers, great on others, is flexible as all get out with accessories, and still holding it's value 50 years later. A damned good performer that will only get better as it continues to mezmerize new owners.

Larry
 
Larry,

That is awesome with the Torsk!!

Yah I saw where she and the Constellation both went in for dry dock repairs.

The Vol's are on the boat every Saturday. Come on down and I'll give you the Nickel tour. get there before 10am. (Even the locked areas that no one else gets to see).
The boat opens at 10 and all non visitor areas have to be locked.

I will take you up on that. I have taken the tour in the past but it was a long time ago. Amazing.

Frannie
 
Larry,
That's a very honest and useful assessment of the three pieces.
In defense of the solid state units, I think they need to be run for a long time before everything inside charges up properly and they sound their best.
My impression is that the solid state units are very nice, voiced similarly, but to take advantage of the technology and be more spectacular sounding in the showroom. Listener fatigue sets in with the ss units where it doesn't with tubes. That's why I've gravitated towards tubes and never gone back.
I'd like to hear your take on that when you get roundtuit.
 
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Frannie; let me know when and I'll be there.

Thanks Don. I did let all of them warm up 1/2 hour before A/B/C checking. Over time I've found that the 500TX wasn't/isn't as fatigueing as any of my PIONEER's. The 424/434/1010 are the least fatigueing of the lot. The 790 is the worst. I don't listen to the QX-9900 that much but it seems to fall in with the 434/1010 series. The Early SS Fishers tend to be voiced similar to the tube units of the period (400,500C 800C) with a touch of brightness. I've listened to the Sansui 1000A extensively and it tend to be fatigueing after about 2 hours which is a little worse than the 434/1010 @ 2-1/2Hours. I've noticed I can listen to the 500TX for 4-5 hours straight without fatigue. The longest I've gone with the 400 is 6 hours and my butt got fatigued. :D The 550 sounds like it will fall right about where the 500TX is in the line. But it depends on what speakers I'm using too. I tend towardd the Bozak 207a's with the Tube stuff and the FISHER SS. They tend to get shrill with the PIONEER's even with the High pot turned all the way down. I've got the 434 in the bedroom with a pair of Realistic Minimus 25's on stands about 3 ft from my head. But I end up on Headphones as SWMBO wants to hear the friggin TV. My Koss Pro-4A's are 42 years old and they sound good as the day I bought them in High School. They actually voice better on the tube/S.S. Fisher's than the PIONEERS, and the SANSUI 1000A. For some reason the Sansui sounds more like a Solid State unit on phones to me.

I was listening to some French orchestra doing Ravel's Bolero off the 550-T last night using the PL-7 and shure M55E. Absolutely GRAPHIC!!!! X-rated Daydreams Yum Yum!!!! When done I switched to FM as I listen to the Radio when asleep. My back tolerates the sofa better than the bed, so.......... anyway.. NO FM, just white noise. WTF???? Switched to AM....NO AM. DOUBLE WTF???? Broke out the manual, and diagnosed a possible bad Zener diode in the Power supply as this is the only item that is same between both bands. The 15V supply was non existant at the AM RF, Multiplex, both IF Boards.

There is a 15V-3W and a 24V 3W zener controlling two circuits. The 24V had been replaced by some less than competent "tech". Renewed the 24V-3W with a 25V-5W and the 15V-3W with a 14V-5W(all I had at the time.....about an hour ago). Then I tested the 15V zener. Failed Short. Put it on the DBT and powered it up. HOT DAMN! Got FM and AM again. I'm gonna order a 15V-5W just in case the 14V isn't a good idea. I'm getting 14.54VDC off the Zener and at the Selector switch. This unit powers down the FM and AM boards when in phono and Aux. I think a 1/2 V is within parameters but then again I'm not qualified.......

It's back in the Main System breaking in. I still have 2 lytics to do (4.7uf/50v in the Preamp) but right now not critical. I checked the Center voltage and the idle current before closing it up. After 30 minutes the center voltage was 0.02 +/- 0.01V fluctuation. Idle current was 40.3mv with .2mv fluctuation. BOTH Sides. This thing is tight!!! Damn.


Larry
 
Larry, you seem like just the guy to set me on track. I have recently acquired a beautiful 660T, brother to the 550.

The space where I want to use the 660 does not allow for very big speakers and partially because of that, I'm thinking about trying the ELAC B6s.

Do you think the 660 will have enough power to run the B6s, which are designed for 30-130 RMS watts? Also, they are 6 ohm speakers....is that a problem for the 660?

I don't want to toast my amp trying to push speakers that aren't ideally compatible with the older, low powered receivers.

Thanks.

mick660t.jpg
 
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I'm not familiar with the Elac's. But considering the 550-T was rated for 1 pair of 4ohm speakers at a time, they should be ok. If the speakers are fairly inefficient, don't crank it hard, expecting the windows to shake, or the 660-T to hold together long. Speaker efficiency of 91db is the bottom of the range I would use with the 660-T. 8 ohms would put less strain on the amp than 6 ohms even tho the impedance curve for the speakers is probably all over the map.

Run them with the volume between 09:00 and 10;00 for an hour with the tone controls centered and the loudness OFF. Check the temperature of the output transistors, and the main transformer every 15 minutes. If they get unduly HOT(>150*F) and stay or the temps tend to keep rising, during the hour, the speakers are loading down the receiver too much. Go up to an 8ohm more efficient speaker. I have my 550-T in the bedroom right now running a pair of minimus 7's. 9:00 on the volume will drive you out of the room. Room is 12x15. I don't have room for the larger speakers and the minimus 7's do just fine with the 550-T.
 
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