Getting another 400.

DAMN. Backwards Schematics. Ok. So pull the coax (wht/org and blk org) and the 680's(which are now gone) and everything should be kosher. I'll do that 1st thing in the morning. To make it look better, I'll rip the wht/org and blk/org and move them to replace the one's I put in to the Bass control T-Strip. Then it'll all be original equipment.

Yep the black/wht and wht black connect as you said to pins 1 & 6 via the caps. Leave these alone.

Changes will be made to schematics.

Give me a GM Winton 248A or 278A V16 2 stroke sub diesel and I'll show you how to get rid of skeeters. Mix Citronella oil with the Diesel, and then load up the engine until the Mean effective cylinder pressures are 125% and Fire Dept's for 50 miles around go on Alert. Try that with a Fairbanks Morse opposed piston 38D 8-1/8 9 or 10 cylinder and all you'll get is more rpm's and more amps from the genset. NO SMOKE!! 100% rpm redline 720 rpm, 1600 hp. although emergency military power is 900rpm 1800 hp. 30 tons of fun! Yippeeee!!!

Hopefully this is the only problem with it, besides the crappy tubes. Gonna have to get some new tubes as I'm robbing peter to run paul.

thanks Dave. You keep amazing me and the group. And we're HUMBLY Grateful!!!:ntwrthy::ntwrthy::ntwrthy::ntwrthy::ntwrthy::ntwrthy:
 
Happy to help! If you want to make the unit technically correct, don't forget to move your new coax cables to the Reverb OUT jacks. I believe they are current connected to the Reverb In jacks.....

Your military mechanical background Larry is nothing short of stunning......... My only question though is how exactly is it that you KNOW about the trick with the Citronella oil in the sub engine.....huh? Bet that stunt took out a lot more than Skeeters!

Dave
 
4th Gen Navy/USMC. Was a Corpsman. Dad was a RD then ET (Radarman then electronic Tech (Navigation)). He was on subs back in the 50's thru 1969. Mainly Diesel boats with a Polaris boat mixed in. Growing up around Diesel boats imparts a certain mindset. Then going in and attached to a Misile boat as all the diesel boats were being de-commissioned by the time I went in. Plus 18 years volumteering on ex USS TORSK in Baltimore, doing about everything imaginable including diving tanks that aren't much bigger than an 80 Gallon water heater, you learn the little tricks that you can pull on the Surface guys (read Destroyers, etc.).

The GM 248 and 278's have a tendency to smoke when loaded down. If you load them up slowly it's not that noticible. But load them up all of a sudden and the smoke is amazing and they will continue to smoke until unloaded. The most a Fairbanks would smoke is very light and almost un-noticible. They did have a bit more when started up on a cold day but not much more than warmed up. A coupleof boats in Norfolk would dump citronella oil in with the diesel in the day tank during the summer. One boat injected it into the exhaust piping while the boats idled during battery charges. Equalizer Charges were the pits. Take the battery down to barely readable on the Hydrometer, and then put a high charge on it using 4 engines and taking off an engine at certain points until they were down to a finishing charge on one engine. The Hydrogen they produced was phenomenal. POMODON experienced a battery explosion in 1955 while doing an equalizer charge in the yard. Too much hydrogen and the meters were wired up wrong , showing a normal level. 8 Sailors were killed and many injured.

This is TORSK in Winter of 62, right after an engine overhaul. She carries Fairbanks, and at that time the rings hadn't seated and she smoked for a few hours until the rings seated. GM boats smoked worse than this tho.
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BACK ON TOPIC! Got the wiring finally set up correctly. Tape Monitor works as it should now.

Another problem has reared it's ugly head. NO SOUND/NOTHING from Right Channel. So I broke out my cheapy little CIE 10mHz Single input scope, using tuner as a signal source, and started at V10. Compared Pin 1 output with Pin 6. OK. Next up C77 on pin 1 and C78 on pin 6. Input to both is good. Output on C-77 is = to input. C-78 is different story. Input is fine on C-78. But NOTHING on output. NADA, ZILCH, DEAD! FLAT LINE!! So thinking the cap is opened up, I pull another and test it 1st. 21.56nf (close enough). Install and turn on. NOTHING ON THE RIGHT SIDE.

V-10 input at pins 2 & 7 are equal.

Tube Voltages for V10 and V11 as above. B+ on pin 9 on output is 392vdc, Screens on Pin 1-7 is 348. Input(wall voltage is 110V out on the porch) TheV10/V11 pin 2 and 7 voltages were fluctuating as I was using the tuner as a source.

I swapped in some known good Tele's from my 800'c and no change.

Gotta go repair a front deck next door (concrete). Back later.

Larry
 
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Larry -- The output of C77 and C78 go directly to the Reverb IN jacks. Make sure the one for the right channel is not pushed in so far as to short to the jack's ground sleeve. If that is not the case, then next, remove the jumper for the right channel completely and see if you then have a signal on the output of C78. If you do, then the problem exists from the Reverb OUT jack and beyond. The problem will show itself as a short if removing the jumper then produced a signal on the output of C78. This should be fairly simple to find.

Dave
 
The jumpers for the REV have the S.S. plastic shouldered washers (2) that keep them from bottoming out. I did pull the RIGHT Jumper and the signal after C78 came back. I took a jumper wire (alligators at both end) and tried jumping at various points until I got sound @ pins 1 & 3 on the P.I. tube.(which proved out the output on that side. Hot Damn!) Tried the input side of th P.I. tube, but no dice. Even shorting across the center pins on the volume control just drops the volume on the LEFT side by about 1/2 with no corresponding rise on the right side.

I did notice that the wiring on and around the Loudness switch looks real hinky. Pins are bent in odd ways, etc. I'll go ahead and rebuild the wiring/cap hookup's, etc. and may put in a new switch from the aforementioned 175-T Donor. Everything else from the REV IN jack to the bass/treble PEC's and all the way around to the P.I. tubes looks good.
 
OK: For starters, chalk up another one to the Fisher draftsmen: On the early and late version schematics of the 400, the Reverb "IN" and "OUT" jacks on the schematic are labeled backwards. Everybody correct your schematics! This mistake has definitely contributed to the confusion here.
.....

The overall problem is do "IN" and "OUT" refer to the unit so labeled (the receiver) or to the external reverb? The "OUT" jack could be "out" from the receiver or "out" from the reverb to connect to the input on the receiver.

Of course, a given manufacturer should be consistent throughout the product line.
 
And that's the problem. Fisher wanted to be consistent, and was for the most part, but got all the 400 schematics backwards. As built, the Reverb OUT jack on any Fisher receiver or amplifier represents the signal FROM that unit going to the SpaceXpander. The Reverb IN jack then represents the return signal being applied to that unit from the SpaceXpander.

Dave
 
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This morning I replaced the Loudness switch. Noted that the affected channel's slider had come out of the housing and was shorting to the chassis. (Good News???) Replaced it with a switch from the 175-T. Had to wrap the wires around the posts (no holes on the ends as FISHER was wirewrapping posts at this time) then soldered them on.

Fired it up and had signal all the way up to the P.I. Tube @ Pin 7. The 2pf cap showed signal on one side but not the other (comparing with opposite channel showed signal on both sides.) Pulled one side of cap and checked value. 260pf or .260nf. I'll get 2 new caps (C89 and 90 on 48001 and up manual). Happened to look at the top side and noted that the tube had gone to air. Replaced tube and tried again..

:banana: SUCCESS :banana: ! Well Sort of. I've got sound from both sides:thmbsp:, but the RIGHT SIDE volume is approx 1/2 of that of the LEFT SIDE:no:. Balance controls to approx 3:00 to Balance out. Figure with all the WEAK signal and output tubes that this will correct itself somewhat when I get them. I did jumper the center lugs on the volume control and the volume increased on the right. Which means if I remember right, that the problem is BEFORE the volume pot.

But She's running:music:and that count's for a lot right now. :tresbon:

Now to go cut some grass for tube $$.

Larry
 
I rolled the tubes on it, and got equal volume between sides. Westinghouse's on the tone and voltage amps, GE's on the P.I.'s, A magnavox and an RCA on the phono(these are the worse two). The three MPX tubes are a Toshiba, Sovtek, and a amperex. Best separation I've heard out of a FISHER.

TWEAKED the tuner and it's pulling all kinds of stuff, loud and clear on a dipole.

Once the 7868's Ive' ordered, and the new 12ax7's I'm gonna order get here it should be a lot better.

Put it in phono, Aux, or Tape head, and cracnk it up to 11 and NOT A PEEP. This thing has no Hum, or buzz, or HISS. It's DEAD QUIET! Finally a FISHER that DON'T Talk Back.
 
Discipline Larry. It's all about discipline. You've got to let it know who's in charge! :)

Dave
 
I rolled the tubes on it, and got equal volume between sides. Westinghouse's on the tone and voltage amps, GE's on the P.I.'s, A magnavox and an RCA on the phono(these are the worse two). The three MPX tubes are a Toshiba, Sovtek, and a amperex. Best separation I've heard out of a FISHER.

TWEAKED the tuner and it's pulling all kinds of stuff, loud and clear on a dipole.

Once the 7868's Ive' ordered, and the new 12ax7's I'm gonna order get here it should be a lot better.

Put it in phono, Aux, or Tape head, and cracnk it up to 11 and NOT A PEEP. This thing has no Hum, or buzz, or HISS. It's DEAD QUIET! Finally a FISHER that DON'T Talk Back.

Congrats on the progress Larry, I have constantly read all the positive threads about the 400 over time, but never actually listened to one before getting mine. I knew that mine was worthy of a total restoration so that it sounded as good as it looked. The 400 has rapidly become one of my favorites, (which I was warned about :D) I am certainly pleased beyond my expectations. :yes:

I look forward to your final repaort when all the new tubes are installed.
 
Steve; I look at a 400 as a downscaled 500-c. It's got a personality all it's own. To me it's not as "in your face" with the midranges compared to the high's and lows as it's bigger brothers. It can be a bit shy in the bass dept depending on your speakers. The 7868's I feel are more refined sounding than the 7591's and I think that's what has everyone saying the 400 is "to die for" in a sense. I like it for it's simplicity and the fact that although it may be a downsized unit, it's not giving anything away to the 500 and 800 series, except a couple watts at the output. Plus the old lady likes it because "it's CUTE"!

It does everything you ask of it well within it's capabilities, and with some mods can go some extra yards. It doesn't have any real faults other than the classic stuff we've already covered in most of the rehab threads and here, but they can and are being overcome. And for a 52 year old (at most) it's a kick ass little receiver that has a lot going for it.

Larry
 
Steve; I look at a 400 as a downscaled 500-c. It's got a personality all it's own. To me it's not as "in your face" with the midranges compared to the high's and lows as it's bigger brothers. It can be a bit shy in the bass dept depending on your speakers. The 7868's I feel are more refined sounding than the 7591's and I think that's what has everyone saying the 400 is "to die for" in a sense. I like it for it's simplicity and the fact that although it may be a downsized unit, it's not giving anything away to the 500 and 800 series, except a couple watts at the output. Plus the old lady likes it because "it's CUTE"!

It does everything you ask of it well within it's capabilities, and with some mods can go some extra yards. It doesn't have any real faults other than the classic stuff we've already covered in most of the rehab threads and here, but they can and are being overcome. And for a 52 year old (at most) it's a kick ass little receiver that has a lot going for it. Larry


You explained it very well Larry, when I picked up mine from Dave, he let me and my brother listen to it through headphones. I could tell he was proud of how good he got it to sound, but listening to it really proved the point. I'm super stoked to have it along side my other Fisher's.

:ntwrthy: 400
 
Here's the ALMOST FINAL underneath shot. Last thing to be done before tubes arrive is plan on moving BALANCE/BIAS BOARD to bulkhead where new P.I. pots are epoxied to bulkhead.
100_4787-a.jpg


Work done.
Rebuilt Power supply acounting for Bias/bal board.
Coupling caps replaced in most all circuits
Film caps replaced in P.S. .01uf 600v (C-80) and other values.
Lytics replaced thruout including MPX, POWER SUPPLY, and various others in unit. Various Nichicon UPW, UKL, UHE, UPM series caps.
CAN CAPS REPLACED with Hayseed Hamfest CAN's.
New Silicon Rectifier. (8A 400V Fairchild; Mouser # 512-GBPC3504W)
Screen staility resistors added. 100 ohm
Grid Return resistors changed to 200K ohm
Output coupling caps replaced with .082uf 630V DME's.
The garrote removed from the P.I (120K resistor removed from pin 3 of both P.I. tubes)
Aux/Tape Bleeder Removed. Cut out R/C between Aux and Tape Mon jacks.
680K resistor on REV in/out removed.
Tape Monitor Mod done (rerouted REV OUT and other cables to allow Tape Monitor to output same level as AUX.
Cathode Resistors on pin 5 of output's 10 oHm to chassis ground

New P.I. Pots (Bourns Single turn 50K) 3362P
New diodes in P.S. 1n4007x2
Inrush Limiters both sides CL-90
X-Y rated .01uf 1kV safety cap. KEMET 80-R413I2100DQ00K
Replacement of Loudness and Tape Monitor switches (parts from 175-T donor)
Tuner tweaked by use of KM-60 manual method without test gear.
GOOD USED quad of EH7868's from Eduarsan1(LUIS).

Multiplex De-Emphasis Mono and Stereo reset by use of resistor change.
MONO to 39K(R28).....STEREO to 16K (R222-223)

C210 replaced. 1uf 400V DME
C221-222 replaced. .047 400V DME

470K resistor in EM84A socket replaced.
Tuner Variable cap (air gap cap) blown down and sprayed with CRC QD Electronics contact cleaner.
Tube socket's DeOxited and the pins re-tensioned
Controls DeOxited, and final spray with DeOxit Gold.

In the end result, in spite of damned near dead output tubes and marginal 12ax7's it does sound pretty damned good. Probably get a pair of Sovtek 12ax7lps for the phono and T.S. 12ax7's for the voltage amps/Tone Amps and the P.I.'s. They should sound good with the EH7868's.
 
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The EM84A tube wasn't responding, also it just barely lit up the edges of the target area when open. I had a couple of spares (em84A and 87A). None of the 84A's would do anything. The EM87A closed and opened as it should. I had already replaced the 470K resistor in the EM84A socket (in case anyone is wondering where R26(early version 400), or R26(late version 400) is located.) Surprisingly they are the same part # on both schematics. I hooked up my spare 49A/49T set from a C.E. VIII Apple Scruff gave me to verify operation. All operated as in the 400.

So an EM87A (6HU6) is running in the 400. And I'll add a couple of EM84A (6fg6) to my ever growing list of tubes needed. Jeez!

OUTPUT Tubes cleared the International Serice Center (USPS)(Read Customs and Immigration), and after a week of package shaking, X-rays, drug sniffing dogs, and klutzy sorters dropping pkg's indiscriminately it cleared the distribution center in Miami bound for Baltimore, probably by way of Boise, Idaho, Peoria Ill., Albuquerque,n.m., and Montpelier Vt. I'd be surprised if they arrive while I still have some color in my hair other than silver. (Can you tell I DON'T like USPS?)
 
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.....

bound for Baltimore, probably by way of Boise, Idaho, Peoria Ill., Albuquerque,n.m., and Montpelier Vt. I'd be surprised if they arrive while I still have some color in my hair other than silver. (Can you tell I DON'T like USPS?)

FedEx ain't no better. They managed to drop a box causing highly visible damage to an eBay CD player. On closer inspection, a small object, probably a bolt, (looked like a screwdriver hole) had punched through the box, through an additional layer of corrugated cardboard the seller had used to reinforce the corners, through 2 inches of paper, several layers of bubble wrap and into the corner of the front panel. Seller could not work from my photos but was willing to take it back for full refund. However, after checking the unit more closely, I decided to keep it and work on that corner carefully with files. The internal damage was all easily fixed, mostly front panel buttons that were rattling around inside with no damage. When finished, I'd have to point out the defect for you to notice it. The sharply squared lower right corner is now slightly rounded.

Back in the 1970s, I had a manager that had the idea of preparing a package with the address showing through a window on top. Then every few days, a timer and mechanism in the box would roll the paper to change the address. The last address would be yours. Then you would see everything the package had been through while going through Boise, Peoria, Abq, and Montp.
 
Larry

@ today August 9, 2015 , 5:37 am the tubes are LINTHICUM HEIGHTS, MD 21090.

I´m really ashamed for this!!!
 
Don't be. Linthicum is the next town bordering Glen Burnie. It should have been sorted at G.B. and put out for delivery this morning. I blame USPS and Customs. When they really want to be obstinent, you might not ever get it. I remember when Homeland Security was set up. All of a sudden you had a bunch of goons with powers that exceeded anything prior to 9/11,except special forces units with a "Kill everyone and let God sort them out" R.O.E. . And it went to their heads, especially at the airports. But the opposite is true too. They needed so many bodies that they were taking some that could barely read,write, or tell you coherently their own name. Typical Go'vt employees now. Do the job but do it slow enough to get overtime justified and keep them(meaning us) coming back for more whether we like it or not. If you are the only game in town, you can do about what ever you want and get away with it.
 
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