dynaco stereo 400 manual

dynaco stereo 400 manual LINK 1 ENTER SITE >>> http://gg.gg/11fu70 <<< Download LINK 2 ENTER SITE >>> http://inx.lv/CnG6 <<< Download PDF File Name:dynaco stereo 400 manual.pdf Size: 1593 KB Type: PDF, ePub, eBook Uploaded: 15 May 2019, 23:47 Rating: 4.6/5 from 671 votes. Status: AVAILABLE Last checked: 8 Minutes ago! eBook includes PDF, ePub and Kindle version In order to read or download dynaco stereo 400 manual ebook, you need to create a FREE account. ✔ Register a free 1 month Trial Account. ✔ Download as many books as you like (Personal use) ✔ Cancel the membership at any time if not satisfied. ✔ Join Over 80000 Happy Readers dynaco stereo 400 manual Dynaco answered the challenge with the Stereo 400 power amplifier. It was conservatively rated at 200 WPC intoWhen it came out, that much power in an amplifierThat's why they included the Dynaguard power limiting system.to keep speakers from goingIt's too big to scan, and pretty tough to find online. Each picture isIf you zoom in, you can see all the detail you need to see. It was a beast with 8 output transistors per channel, or 16 output transistors in total, thus. It had a two speedIt had LED power metering with aIt was the no-holds barred power amp. Stereo 410 Assembly and User's manual, DMJ collection. I found this out recentlyThis one has the metering kit. The left channel Dynaguard light was permanently on.Upon looking at the PC-29 in my Stereo 400, I quickly found thatThat manual was purchased in a pilgrammage taken to Dynaco in Blackwood, NJ in the mid Contrast this with the Note: It's a large, high res file,It's a large, beefy relay with a 48 Volt coil and big contacts rated at 15 Amps. Still, withThe most blameless suggestion I could find was to clean it with laser printerI pulled the alcohol soaked paper through the contacts on December 29, 2012. We'll see how longIt uses a pair of sealed relays with contacts rated at 16 Amps. ThisWe've named this the RY301 kit after its designation in Stereo 400 schematics. Here'sOrder the Stereo 400 Relay Kit.The Stereo 400 and 416 were there at. Manufacturers started throwing 10's of thousands of microfarads intoThe C-100 capacitor bank was the ultimate answer to the microfarad wars. You could addI added a few more annotationsIn the course of that, I've written a circuit description that contains a mystery, so theQ3 on the PC-29 had gone bad. I replaced it with a 2N3904, and Everything with a Stereo 400 is a bit of an adventure. This was, too. The enclosed video shows the process of changing the fuse holder. I haveJust send me an email and we can work it out. Each meter has two bulbs. http://www.colegiosantarosa.com/uploads/imagem/coolpix-s6600-manual.xml dynaco stereo 400 manual, dynaco stereo 400 service manual, dynaco stereo 400 manual, dynaco stereo 400 manual pdf, dynaco stereo 400 manual download, dynaco stereo 400 manual instructions, dynaco stereo 400 manual diagram. The right meter had one bulb that still worked.The low voltage transformer winding puts out 15 volts RMS (open circuit) between the grounded center-tap and theThis is one that I'm doing a bit of restoration on. The mainI think I might be able to put some white LED's in there. Or, I wonder.is this theThe assembly method is a bit modified from the classic way we've done itWe then used 1 blue light board to replaceThis is shown in the next picture.The room has normal daylight illumination.The design is very similar to the Stereo 400, and might be used as a guide for the 400 also. The Stereo 416 is similar, but it hasThe design is very similar to the Stereo 400, and might be used as a guide for the 400 also. The Stereo 416 is similar, but it hasThese voltages apply with no input signal, and the bias current adjusted for 75 mA in the output transistors. These voltages are a rough guide. In some places, small changes are notIn that configuration, it was rated to produce (monophonic) 600 Watts into 8 Ohms. The MBI-400 document showed how to make the conversion. They include 46 transistors, 47 diodes, 2 silicon controlled rectifiers, and 4 integrated circuits. The entire main amplifier is direct coupled. To this end, Dynaco has included more separate protective systems and features than have ever been employed in such a product. It has been designed as two independent 200 watt (at 8 ohms) amplifying channels with a common power supply having a high degree of inherent regulation. All files are provided under strict licence and reproduction without prior permission or for financial gain is strictly prohibited. If you have additional documentation please consider donating a copy to our free archive. Also Dynaco preamplifier and Dynaco loudspeakers and Dual 1249 record player. Very good sound. There were two fusions on the front. I think I had fusions of size 2 amp. To protect the loudspeakers when I blasted Pavarotti. This was very helpful. http://ceramicus.ru/userfiles/coolpix-s6400-manual.xml I just purchased this amp, and find this information Very helpful. Thanks again, moduck. That seemed to be a significant sound improvement. To purchase Stereo 400 spares or accessories, please contact the company via their website or visit an authorised retailer. Consumer Electronics, If you follow any of those links and end up acquiring a manual, it will not be from us. Here is why we may deserve your business. 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If you want multiple Whether your email is to order Tell us EXACTLY You may findIndividually-assigned Describes modernization procedure for a popular Overall quality If an item has a description and Price Code, then CLICK THAT PRICE PRECISELY identify the item you want with company brand. If you want multiple Whether your email is to order Tell us EXACTLY You may findIndividually-assigned Overall quality Overall quality is Very Good to Excellent. Original Pictorial and Informational Insert not Overall quality is Very Good to Excellent. The original manual and the Pictorial We make almost no Overall quality is Good to Very Instructions for Assembly and Overall quality is Good to Very Good. Overall quality For Serial. Overall quality is Very Good. Overall quality is Very Good. https://fiaxell.com/images/canon-ixus-125-hs-manual.pdf Instructions for Assembly and Note: Pictorial Diagram insert Overall quality is If an item has a description and Price Code, then CLICK THAT PRICE PRECISELY identify the item you want with company brand. If you want multiple Whether your email is to order Tell us EXACTLY You may findIndividually-assigned Instructions Overall quality is Very Good. Overall quality Overall quality is Very Good Overall quality is Very Good Our original has some mold or We’ve extensively edited Overall quality is Good to very Good. Overall quality is Very Good to Excellent. Overall quality is Fair to Good. Includes schematics, The original comes with a large poster-sytle We reproduce it on (4) 11in x Overall quality Normally folded and mailed in ordinary business Our original manual has a cut No content is missing or particularly damaged. A previous owner The unit image Other than that, overall quality is If an item has a description and Price Code, then CLICK THAT PRICE PRECISELY identify the item you want with company brand. If you want multiple Whether your email is to order Tell us EXACTLY You may findIndividually-assigned It makes a difference. Seekers of truth mayImages may be used with. Please use the form below to log in, or click the 'sign-up' tab to create a new account. Please let us know if you have any questions or comment on how we run Hifi-Manuals. The ST-400 was first manufactured in 1973. The owners manual is used as an reference guide, instruction manual and instruction book. The service manual functions as a repair guide for troubleshooting and sometimes contains tips for refurbishing and modifications. The schematic is a technical drawing or diagram of your system, a perfect supplement to the Service Manual. This data is collected and thus shared with Google. Got it. It may not display this or other websites correctly. You should upgrade or use an alternative browser. I'd never seen one 'in the flesh', but had heard a fair number of good things about it and the rest of the series over the years. The amp had a mystery wire sticking out of the side, which I later realized had once been connected to a fan of some sort. I've owned numerous Dynaco equipment over the years, but other than a couple of PAT-4 preamps, all of it has been tubed ( ST-70, Mark IIIs, ST-35 ). Also, the vast majority of the component-level work I've done on vintage gear has involved tube equipment. Additionally, this ranks as the largest amplifier I've owned thus far, displacing a Pioneer SPEC-4 in that position. Regardless, I feel good about my prospects of being able to fix this ST-400, since it was designed to be built as a kit, and lots of documentation is available about it. Also, I have a fair amount of test equipment around here, including a transistor checker. Anyway, as mentioned earlier, I was able to give it a listening test before purchase, which showed some (hopefully) minor faults. When powered up for the first time, the pilot lamp came on, as did both of the lamps behind the smoked plastic window, which I later learned are the DynaGuard indicators (the switch was turned to OFF, and cycling the switch through the settings has no effect on their illumination), and the relay clicked. Once fed with a signal, I got audio from both channels, though some distortion could be heard in the right channel. When I checked the DC offset, the right channel showed -22mV when first powered up, which later fell below -1mV, while the left channel shows a pretty steady 18-19mV. Granted, I didn't give it a full 15 minutes to warm up, but things seemed to get settled in fairly quickly. In summary, my question is as quoted in the title. As mentioned before, I have little experience working on solid-state equipment in general, though I think it's time I learned how. My guess is that new capacitors are needed, along with whatever drifted resistors there may be, but I'd rather not just shotgun everything or replace all the boards with new ones (as shown in my ST-70 restoration article, I like to give the stock circuitry in these things a fair shake if at all possible). Anyway, here are some pictures of the amplifier: The front panel. Seems to be in pretty good shape overall. The rear panel. The presence of a serial number sticker makes me think that it was factory-wired, as was the case with Dynaco's tube equipment, but I don't know if that's the case for the ST-400. The inside of the cage. Seems decently clean overall, and I didn't see any obviously-burnt components or whatnot. The copper-colored coils near the fuse holders make me think it's an early version, as discussed in this article about a ST-400 modification (unless it was referring to a different coil-wrapped resistor). The 'mystery wire' mentioned above. Both leads of the zip cord are connected to a terminal strip near the power switch; one to a primary lead of the power transformer, and the other to one of the leads from the power switch. I removed some of the electrical tape, and the two bare ends are isolated from one another. Anyway, thanks in advance! -AdamAlso, download the service manual. If you can't find it I can email you one. JimI am terrified at the thought of plugging it in. Heck, I am terrified at the thought of taking the cover(s) off. Dang solid state stuff is so complicated, and -- best I can tell -- it is pretty much guaranteed not to work at this late date.Also, download the service manual. If you can't find it I can email you one. Jim Click to expand. I did download copies of the service manual from both HiFi Engine and Update My Dynaco, though I'm not sure yet if either one is fully applicable to the unit I have. I'm not sure how many revisions were made to the ST-400 over its production lifespan.I am terrified at the thought of plugging it in. Heck, I am terrified at the thought of taking the cover(s) off. Dang solid state stuff is so complicated, and -- best I can tell -- it is pretty much guaranteed not to work at this late date. Click to expand. In any case, the nice thing about this Dynaco solid-state gear is that it was designed as a kit, so instructions for troubleshooting are widely available (as it was an expected part of assembly). What would be the best place to start in trying to track it down. I do own an oscilloscope, along with a fair amount of other pieces of test equipment, including signal generators and frequency counters. -AdamUsing revised schematic from hifiengine Suggest supplying amp with low level 1kHz sine wave and use CRO to identify distortion. Dynaguard switched off.You have a nice clean looking sample there. I'd advise focused efforts to fix what is broken, rather than wholesale renovations.For what it's worth, I've never worked on a 400 series amp that didn't have a power supply issue. The PS runs hotter than anything else in these amps. With 40 years gone by, it's not surprising.The most common problem is overheated resistors on the drive boards, two of each 1K, 750, and 300 Ohms on each board. Sometimes they are standing on end, early board, or flat against the board, later version. They run fairly warm and the solder joints go bad.My intents are to preserve as much of the amplifier's original circuitry as possible, as I've done with my tubed Dynaco gear. While I'm definitely not one for 'shotgunning', there are some parts which are highly likely to require replacement either now or in the future, such as electrolytic and tantalum capacitors. Once I determine the reason for the right channel distortion and repair it, I will likely go ahead and replace all of those parts, plus whatever else might need replacement, like drifted resistors. -AdamWhat might be the likely cause for this. I'm guessing it's not the case of the distortion, but could it be causing both DynaGuard lamps to light. Methinks the game is afoot, in any case. -AdamClick to expand. I shall have to examine the PC-30 board in my amplifier carefully to determine which version I have, and to make sure I have the proper manual version for my amplifier. -AdamAlso, if you switch the dyna guard off, there should be minimal current draw, are the voltages the same. Agree, that zener has probably had a hard time and is near death.While the OP was about distortion in one channel, think that we all agree that psu voltages should be normal.With one lead of my DMM connected to the chassis, D304 reads 0V at the non-striped end, and 12-13V at the striped end. However, D305 reads -23V at the non-striped end, and -10V at the striped end. Given that this still works out to a 13V difference, it would seem that D305 is doing its job to some extent, though perhaps not correctly. What would this seem to indicate. Is the zener at fault, or could the issue lie elsewhere. Again, thanks! -AdamHowever, D305 reads -23V at the non-striped end, and -10V at the striped end Click to expand. Talking 1-2Volts at most. The zeners appear to be 12 or 13Vdc. So -23 volts is a red flag, means channelling 10 volts, they would simply change R307 so it would burn up these volts. A greater red flag is that one end of the zener is connected to ground. At D305 you have -23V (input, too high) and -10V, this should be 0V, maybe you have an earth issue. You can repeat for D304 stripped end and chassis. Maybe a burnt track near D305 stripped end. For a better experience, we recommend using another browser. Learn more Facebook Email or phone Password Forgotten account. Sign Up See more of VTA Tube Amp Kits on Facebook Log In or Create New Account See more of VTA Tube Amp Kits on Facebook Log In Forgotten account.Below is a link. to a new solid state rectifier (in kit form) sold by Rick Green from Stuart, FL. This rectifier is similar to the Weber WS-1. Mr. Green's rectifier is made with heavier duty diodes than the Weber WS-1 and does have a thermistor included to give a delayed start. You can put the kit together in about 30 minutes. This SS rectifier will work well with any VTA amp or any original Dynaco ST-70, Mark II, Mark III or Mark IV amp. Check out this new rectifier kit at the Ebay link below. A couple of mistakes were found in the text. Anode should have been Cathode and pin 6 was omitted.Built a pair of VTA M-125 mono blocks with KT-120 tubes. Putting out 125 wpc tube power and weigh about 32 lbs each. Purchased them in kit form. Took about 10 hours each to build from scratch. Had been trying to find a perfect matchup with my Gill Audio Alana preamp and was running in to impedance issues with Class D amps and also a Schiit Vidar. It had only 22k Ohms impedance and my system was very quiet. These mono blocks have 270k each. Don’t think I’ll have any heat issues in my living room this winter ?? They sound absolutely amazing and punch way above their weight class for the price. Bob is awesome to work with. Answered all of my questions and also immediately sent out a replacement power switch when I needed one. Nice work Tom ! You have a great music room.Just go to the link below and click on the manual you wish to download. We have on this web page. 1. Dynaco FM-1 mono tuner manual 2. Dynaco FM-3 stereo tuner manual 3. Dynaco FMX-3 multiplex manual for the FM-3 4. Dynaco Mark 2 power amplifier manual 5. Dynaco Mark 3 power amplifier manual 6. Dynaco Mark 4 power amplifier manual 7. Dynaco Mark 6 power amplifier manual 8. Dynaco PAM-1 mono preamp manual 9. Dynaco PAS-2 stereo preamp manual 10. Dynaco PAS-3X stereo preamp manual 11. Dynaco PAS-4 preamp owners manual 12. Dynaco SCA-35 integrated amplifier manual 13. Dynaco ST-35 power amplifier manual 14. Dynaco ST-70 power amplifier manual 15. Dynaco ST-70 Series II power amplifier manual 16. Dynaco FMA-2 insert amplifier manual I also have here on my computer a fairly complete collection of all the Dynaco SOLID STATE manuals. See solid state manual list below. 1. Dynaco AF-6 stereo tuner manual 2. Dynaco FM-5 stereo tuner manual 3. Dynaco PAT-4 preamp manual 4. Dynaco PAT-5 preamp manual 5. Dynaco SCA-50 integrated amplifier manual 6. Dynaco SCA-80Q integrated amp manual 7. Dynaco SE-10 equalizer manual 8. Dynaco ST-80 power amplifier manual 9. Dynaco ST-120 power amplifier manual 10. Dynaco ST-150 power amplifier manual 11. Dynaco ST-400 power amplifier manual 12. Dynaco ST-410 power amplifier manual 13. Dynaco ST-416 power amplifier manual 14. Dynaco DSC-1 stereo control unit 15. Dynaco QD-1 Quadaptor manual 16. Read 1348 times.These are FREE for downloading. Even though you may not own any Dynaco solid state gear, some of these manuals make interesting reading. Check the link below. I have here the following Dynaco solid state manuals. 1. Dynaco AF-6 stereo tuner manual 2. Dynaco FM-5 stereo tuner manual 3. Dynaco PAT-4 preamp manual 4. Dynaco PAT-5 preamp manual 5. Dynaco SCA-50 integrated amplifier manual 6. Dynaco SCA-80Q integrated amp manual 7. Dynaco SE-10 equalizer manual 8. Dynaco ST-80 power amplifier manual 9. Dynaco ST-120 power amplifier manual 10. Dynaco ST-150 power amplifier manual 11. Dynaco ST-400 power amplifier manual 12. Dynaco ST-410 power amplifier manual 13. Dynaco ST-416 power amplifier manual 14. Dynaco DSC-1 stereo control unit 15. Dynaco QD-1 Quadaptor manual 16.I've purchased copies for most of my solid-state equipment, but the ST-120 manual is a little harder to come by. The scans are outstanding. Harry Maryville, Tennessee Happy owner of both tube and solid state Dynaco gear. It's been awhile since I encountered any SS Dyna, but this resource may see me snagging the best I see if and when it crosses my path.My sincerest thanks! Bill Given the great service you are providing, please let me know and if I have paper copies in my archives I will snail mail them to you for your scanning and posting. Either tube or solid state Dyna units. Best regards, Frank Van Alstine The only two manuals that I know I DIDN'T have were two solid state manuals. 1. The SCA-50 solid state integrated amp 2. The QSA-300 which is a 2 or 4 channel solid state power amp I have recently located these two manuals but I have not had the chance to scan them. I will scan them within a couple of weeks and have Roy Mottram post them with the others. Frank - If you check the manuals listed on both the tube and solid state pages and you notice one that you have that is not listed there send me a PM and I will send you my address. Thanks again, Bob Latino By using our site, you consent to the use of cookies by us. Or share your ideas and experiences. AudiophileI have acquired a Dynaco 400 stereo amplifier and it has some problems. Upon pulling off the top cage cover and before plugging it in to my dim bulb tester I noticed it had a transistor that was hanging off the PC-29 board on the very top by one metal leg only. I looked at the service manual and it was labeled Q6 on page 39. Upon searching for the part number I could not find it listed. I searched again and on page 23 found the number Q106 a transistor MPSU56 and the part number 567043. Am I correct in assuming this is the correct transistor to replace the one that is hanging off. There are no numbers on the one in the amp. I really can't go any further until I replace this part. I also plan on re-capping it. In normal operation the relay driver grounds the low end of the relay RY301, allowing current to flow through the relay coil, and thus closes the relay to connect the power amplifier to the loudspeakers. If there is excessive DC sensed at the output of the power amplifier, the relay driver circuit senses this and shuts off, thus opening the relay and disconnecting the loudspeakers to prevent damage. Later it was increased to reduce premature triggering of the relay circuit at high output levels. I would suggest checking the amplifier WITHOUT speakers connected, first by the Preliminary Tests on Page 27 of the Dynaco Stereo 400 manual. If you get it powered up, especially check the DC voltage at eyelets 10 and 11 on PC-29. These are the centerlines of the complementary-symmetry output stage (eyelet 10 right channel, eyelet 11 left channel). I am thinking that someone may have messed with that Q106 because the relay wasn't closing. But the ACTUAL reason for the relay not closing to begin with would more likely be an output stage failure. AudiophileThat helps a lot. If they are already blown, you probably already have shorted output transistors and very likely, damage on the driver boards. I'd power up such an amp through a VariAC but you're going to power it up through a light bulb to absorb excess current, as a precaution. Good luck! GP49 I am going to power it up as soon as I get the part installed I was referring to in my first post and plan on using a dim bulb tester. I am going to order that part today along with some other items I am in short supply of. Most of the time if a non-Dynaco technician replaced the fuses, they'd use glass ones because that was what was usually kept in stock. GP49 Joined: April 19, 2006 So far, all of them have 6-ampere AGX type fuses on top of the relay plate. I have yet to encounter one with ceramic fuses installed. MarkAfter looking at them for too long, with no responses from registered letters sent to the owners, I took them home and used them myself. After about ten more years I sold them off and as far as I know, they are still running.Joined: April 19, 2006 Exactly how did you bypass the PC29 board, anyway? If you do this, the Stereo 400 will no longer be usable with the Dynaco PAS preamps; its input impedance will be too low. I disconnected the twisted-pair wiring at eyelets 19, 20 and 22 of PC-29 to eyelets 1 and 2 of each PC-28; and ran an extra twisted pair, one signal and one ground, from the input jacks way down on the heatsink, to eyelets 1 (signal) and 2 (ground) of each PC-28. You could also run that extra twisted pair from eyelets 21, 23 (signal) and 22 (ground) of PC-29 to the corresponding eyelets on each PC-28. Much shorter wiring and easier to do. This change duplicates the operation of the bypass switch on the Stereo 416, in its bypass position. It leaves Dynaguard in operation; since Dynaguard is out of circuit until actually triggered, disconnecting Dynaguard is not worth the effort if it's working properly. Leaving the inputs connected at PC-29 will provide Dynaguard with a signal to work with. You still need to fix the protection and relay driver circuits on PC-29, so this is not an easy way around diagnosing and fixing the Q105, Q106 problem.. unless you want to bypass the relay and depend on fuses to protect your speakers (Dynaco did that on the Stereo 410). I don't recommend it because fuses depend on excess current to blow, and by then your speakers could be fried. GP49 Joined: April 19, 2006 Of course, all of the original transistors have been replaced, presumably with better parts. With the one I built in 1975, aside from the original power switch having developed a short in it, one of my bigger concerns was the 10-watt resistors on PC-30 getting too hot. That question was addressed on this forum earlier, so I might have a good solution for that problem. Back to original point, I have no intention of bypassing anything in any of the ST-400's that I have, although on one I picked up on e-bay last year, I noticed that input volume controls had been bypassed, and also noticed some film caps on the back of the PC-28 boards, I just haven't gotten into any of them yet. MarkDynaco acknowledged that a whole batch of them were bad! GP49 Joined: April 19, 2006 I'm also considering redrilling the heat sink to double the number of output transistors, as the 416 (and some 400's were done, even though I know this could be a problem. Mark I know of one Stereo 400 that was drilled in our shop for the additional TO-3 devices. Frank could be a curmudgeon; he even said that Dynaco stole his Double 400 design for the Stereo 416.right down to an error he made. But he has never, to my knowledge, ever said what that error was. GP49 Joined: April 19, 2006 Original D3, a BZ102, no longer available, now use 2 1N4148's. Older version replaces D8 and D10 with 1N5231B, newer version lists replacing D7,D8, D9, D10,D11,D13 and D14 with 1N4148's. More? OK, how about replacing the DB301 with a GBPC 35 A 800V. By the way, the BC550B's are cheap at Mouser. Mark One problem with working on Dynaco equipment is the transistors that are marked only with Dynaco part numbers. They can make it tricky for a technician in some cases. An early example: in the Dynaco Stereo 120, the output devices were originally identified in the early-production construction manuals as 2N3055, a very widely available TO-3 power transistor. However, a transistor could meet the minimum specifications for a 2N3055 and yet be inadequately rated for operation in the Stereo 120. I don't know how many of those Stereo 120s are still functioning and still capable of being operated today, but I still have two that were used for years as loaners for customers, because they cost me next to nothing and I wouldn't cry if one blew up.