Thanks Tony, I always see techs clean the PCB boards in videos but mine never come out that good because I didn't realize I had to just leave it alone after cleaning and let it self level (evaporate) Another a-ha moment with X-Ray Tony. Great video man.
Hi Tony, I really enjoy your solder and chat time. It was really enjoyable to hear a little about x-ray machines. As a first year Electrical Engineer student, I would really like to see your basic electronics videos made public. Thank you for all your effort in making these videos for us to enjoy. -Rachel
Love the solder chat and looking at it getting done. The little details teach low tech amateurs like me “how-to’s” you are probably not even aware of and consider boring. The potential future basics videos sound good too. Thx Tony, you’re inspiring.
My friend, a little trick I use to help remove the glue without damaging the board, because I don't like seeing scrape marks on the pcb, Now, without going crazy, I heat the glue with a heat gun, trying not to heat any near by components. And if I'm really concerned about any of the components, I'll shield them with some aluminum foil or a piece of cardboard, anything to keep the heat from them. I hope this is a useful tip to others.
Thank you for continuing to share your repair/restoration videos! Regarding sharing the "basic electronics" videos you may make...I would selfishly vote that you share them. Stay well.
Thank you for sharing this video Tony; that Marantz amp doesn't show itself in the wild very often. I'm really looking forward to hearing the soundstage at the final checkout!
Hello Mr. tony! Loving the channel. Your demeanor is very refreshing. One thing I would like to comment on is the trimming of semiconductor leads. I always solder the device first and then trim. This is to mechanically isolate the device from the cutting action to keep the shock on the lead during the cutting action from being transmitted to the device. I've seen devices fail after cutting when the lead was not previously soldered or holding the lead with pliers between the device body and the cutting tool. Just a tip from my 50 years of electronics design, test and repair. It's rare, but have seen devices outright fail or have a high infant mortality rate due to the trimming shock.
Note for the very last part of the video (cleaning the board) I always wipe off the the board after soaking it with isopropyl alcohol with Q-tips. Your method, Tony,, only dilutes the excess flux and spread it across the board and it will remain sticky after the alcohol evaporates.
I for one watch everything you put out so a refresher course never hurt no one ! I have a Microscopy (SEM) background and I remember saying "won't change much, it's the laws of Physics" oh how wrong I was !....cheers.
Thanks for video T. ,,Here benched down with: XTB-video&coffe, + schematic side by side your video. A nice weekend highlight, really enjoying listen&watch. //Have nice upcoming week.
Hi Tony, if you make some basic electronics videos I vote you make them public. We have a 13 year old girl here just starting on electronics so they would be ideal. I know you would make them informative and practical.
Sir, I really enjoy your solder-n-chats. You are very kind to share your time with us. I hope many more folks join your patreon, it’s umpteen times more enjoyable than anything on Netflix :)
Excelente Tony, este amplificador es muy parecido a mi Power Marantz Modelo 300DC, que de echo es de la misma potencia de este, bajare el Manual de servicio de este para compararlos. La etapa de potencia. La fuente es idéntica , un gran transformador con doble devanado. y 4 condensadores de 10.000uF 80V.
@@mattfranklin3622 Hola Matt, bueno te puedo decir que he reparado varios 300DC y los conozco muy bien y por eso te dije eso, nunca he reparado un 1300 DC, pero baje el manual de servicio y los compare, las etapas de potencia son similares , pero no iguales, ahora si hablamos del Marantz 170DC si te puedo decir que son iguales pero con componentes de menor potencia ya que este solo da 80 vatios por canal. Para mi el circuito de la etapa de potencia del 1300DC esta mejor elaborada, pero tiene sus contras donde el 300DC es mejor. Por ejemplo el 300DC esa una fuente regulada con un transformador independiente para alimentar la parte donde esta el par diferencial Q701 (2SK109) y toda esa área en la entrada de la etapa de potencia, esto lo hicieron para que ese voltaje no se viera afectado cuando se le esta exigiendo al power, lo que hace que el voltaje decaiga bastante, en el 1300DC usan el mismo voltaje que le llega a los transistores de potencia solo lo limitan con una resistencia de 10 ohm. Ya por eso es mejor el 300DC. Pero si vemos como en el 300DC hicieron para regular la corriente de Bias, te das cuenta que en el 1300DC esta mejor realizado este circuito. En el 300DC usaron un Termistor (Q722 y Q723 SDT-100) el cual es de 1000 ohm, el cual su valor decae si la temperatura aumenta y usaron el Varistor (Q720 y Q721 MV-1) el cual también varia su voltaje de conducción de acuerdo a la temperatura, bueno te cuento si por mala suerte se dañan estos componentes no los vas a conseguir en ninguna parte, ya eso es una desventaja con respecto al 1300DC. Hay foros que dicen que en Varistor MV-1 se puede colocar un diodo 1N4148 pero este diodo no tiene el comportamiento que tiene el MV-1. En cuanto al Termistor en el mercado se consiguen termistores de esas especificación pero la velocidad de respuesta en muy lenta con respecto a los termistores que trae el 300DC. En el 1300DC usaron un transistor (Q734 2SC1568) que va acoplado a el disipador de los transistores de potencia el cual monitorea la temperatura y regula la corriente de Bias, un circuito mejor elaborado. Por otra parte en el 1300DC el transistor doble Q702 2SC2259, esta descontinuado, pero allí se pueden montar dos transistores de características semejante emparejados. Eso también ocurre en ambos power con Q701 2SK109, también esta descontinuado, pero en este caso se puede montar dos FET 2SK117 emparejados y acoplados térmicamente. Hay foros donde dicen que se puede poner el uPA68H pero no , yo lo hice y no hubo forma de ajustar el 0 voltios a la salida. Bueno espero haberme podido explicar y haberte podido ayudar. Saludos.
The main indicator of quality (and Marantz was ultimate quality) is the concrete block sized power transformers and the HUGE caps ! Talking building demolition there is enough bass out of this thing to wreck a building!
Super interesting Tony, thanks for taking us along. 2 questions: why do you cut component leads before soldering and not afterwards and is the board sticky after the isopropyl has evaporated? Thanks again!
I've often wondered in these direct coupled designs whether something could be added (a zener or crowbar or some other monitor) that would shut down a stage quickly enough to prevent such damage. I used to work on such amps etc in my dim and distant past and remember the horrors of thinking that you have found and replaced everything suspect, only for the same thing to happen again.
Excelente Tony, como siempre, Tony lao transistores 2SA968 y 2SC2238 si tienen los pines correctamente, Base, Colector y Emisor, si buscas un sustituto lo conseguirás igual, no se invertirán.
Loved the talk about the exray. 20+ years ago I received alot of x-rays during cancer treatment and was told I was pretty neat max. X-ray exposure. Today they are not concerned and keeps prescribing more catscans etc. Now I know why they aren't concerned.
I haven't really been doing much on my bench lately because of how much everything is costing now. I'm disable and live on a very fixed income so I really just can't go on the limb to by parts to fix stuff. Although I would love to get my hands on one of these to bring it back to life. I would love to see your training vids.
Crazy price rises in the UK. Some of my regular stock components have gone up by 300% to 500%. Petrol and food have doubled in price. Household energy has increased five fold and business energy by ten fold. Think our business will fold under the pressure, COVID-19 followed by huge energy and food inflation and now our customers are cutting back on orders. When will this apocalypse end?
I loved and agreed with your comment about how many stereos do you need! I love doing the restorations, but I cant listen to them all :) time to donate and sell some off. (Its hard not to get emotionally connected to a restoration and want to keep it)
Yes! that would be practical, even a retired engineer in electronics such as myself would find it a good refresher. I do repair my own items and some consumer jobs, (very relaxing).
Hello tony . I am from Canada . My father was in the RCAF . He had enough rank to sign for tubes and all sorts of items destined for the dump as it was common practice to reorder to spend the years budget so the budget did not get lowered . Most are military spec. made in USA. If by chance there is something you can not source let me know and I will look in my stash . There is even single digit read outs that use filaments . North bay Ontario was the underground NORAD sight. 20 min ride in the bus to get down to the complex . Hope work slows up so you can post more vids . Have a great day EH .
Hi Tony, I have a Sony STR-6065 stereo receiver I do not use. It does work but prob needs some service being its over 40 yrs old. I want to donate it to someone who will appreciate it. Are you interested?
Another Great Video, Thanks Tony one thing though - I am not a fan of the amp. in my opinion it dates from after MArantz reached its peak. it was their flagship amp , but did not have the same build quality as the US model, or the 1180 for example. fancy circuits though. I think the quality of the PCBs and caps illustrate what I think
So of course we must know... when you're replacing capacitors on a piece of x-ray equipment... are you minding the outside foil lead and placing it correctly?? 🤔😜
The 2330B has two varistors screwed to the heat sink that need to be released via screws. No big deal but that's the only way to get the power board to lift up after taking the module out.
Do you think the crosstalk is an important parameter overall?? Do you ever take measurements of channels separartion? Some folks - like Julian Hirsch - don't think it does not import that much, others clain that the less "polluted" channel from the other, the better, providing better soundstage, imaging and liveliness of the music. Could you tell - in a next video - about the Crosstalk (or better channel saparation). Thank you a million.
Hi Tony, you have replaced the 2sc2240 and 2sa970 with ksc1845 and ksa992. Their obvious difference is their collector current rating, ks series are rated to just 0.05mA compared to 0.1mA to the two original transistors. Do you think this is not critical?
The collector currents are 50mA and 100mA respectively (a little typo, but I understand). In some cases, this is a concern, but in this circuit, the collector current will be far below this, as they are driving the base of another transistor and are current limited by the resistors in the circuit as well as the voltage divider bias applied to the base. I am more interested in the voltage rating, as these transistors can have some pretty high voltages (as far as small signal transistors go) on them. On a side note, you will find that pretty often, this will be the case when you compare a "2S" transistor with its "KS" equivalent. This is why you always have to check. It is also why you can't always rely on those "crossover lists" that people post on the forums of electronics/audio websites. It may work for the application that the person on the forum was using it for, but not necessarily for what YOU will be using it for. Good comment!
@@xraytonyb Yo uso el KSA992 ´para sustituir el 2SA872A y el KSC1845 para sustituir al 2SC1775A, suele usarse en amplificadores Marantz de esa época, las características son las mismas.
Hi, Could you turn on subtitles for movies, my english is not good. I use automatic translation and it helps a lot. Your movies are amazing Greetings from Poland
If you do basic videos, be sure to set the context, as in pose a real world issue that justifies the lesson. For instance, no one really want to learn Ohm’s Law, per se, but we might be intensely interested in learning how electricity works. Why are fuses rated as they are? Why are wires sized differently for different purposes? How does a transformer work, and why aren’t they rated in KVA and not by voltage alone? Etc. Etc. Edit: I would be interested in your take on basic electronics . Years ago, I couldn’t find what I was looking for in books, so I took a course in the local community college which changed my life.
That is what I was thinking. Also, How do all the components work together and why, signal flow, a bit on schematics. There are plenty of videos on basic electronics on YT, and they never go beyond the basics.
I'm not that interested in basic electronic videos but one on safety would be beneficial to both beginners and "advanced". For example how to deal with high voltage, high power, xray, ... Apart from lasers, these other safety hazards are rarely discussed on youtube.
Looks like this project is going to take a while...Maybe you could explain the criteria you used to decide on the replacement transistors. I know Vce (max), Beta and Ft play a role but what other parameters do you consider ?
The smaller transformer provides power to the regulated DC power supply board. This board powers the preamp section of the amp. The big transformer only provides the unregulated power for the amplifier output section. Not sure why they felt the need to do it that way, but that's what they did. :)
@@xraytonyb Yo tengo un Marantz 300DC y es igual tiene un segundo transformador para alimentar la parte de entrada de la etapa de potencia con voltaje regulado, pero he reparado otros Power de esa época y usan la misma practica, por ejemplo el SPEC-2 y SPEC-4 de Pioneer, claro es un devanado aparte en el mismo transformador.
Hi how are ya, was just wondering if there’s any interest in a pioneer SX 1250. It’s in working order, after being on for a while the right channel fades, turn volume up a little bit and it comes back.
Another excellent solder and chat as well as learning session in audio electronics. Like the idea of the "led backlight" tester being used on Zener diodes. Especially for the high voltage zeners. Have the Peak, but can see the value of other tester.
You have x-ray employees that don't know Ohm's law? In Norway I don't envision anyone without at least two years in school covering all aspects and then two years apprenticeship getting near one, besides carrying tools and boxes.
Back in the late 1960's, early 70's a schematic with test points and values at each point came with receivers or communication radios..I wonder why this is not the case today ? Ha.
This is a great series Tony I'm really enjoying it! I'm learning so much. As far as the expense of the components going up so much, all I can tell you is to vote for Trump next time... Like an infamous Democrat said many years ago.. "It's the economy stupid!"Apparently the Democrats forgot that...
Please do not kid yourself. Not everything is polarized home politics. It is world economics. Europe is *a lot* worse off in terms of all kinds of price explosions. The cost of electricity is 500% to last year. It’s DT who ruffled up the world wide power balances with the Russians and the Chinese to begin with.
The new Western Electric WE 91E single-ended Triode with two 300B tubes and one driver tube each, plus a single output transformer, and an integrated MM/MC phono stage is $15,000. The original WE 91A was used in movie theaters in the US starting in 1936. Reviewed in the latest issue of Stereophile (November 2022). Gorgeous amp. Edit: The WE 91E also has Bluetooth (USB & RJ45 ports for firmware updates).
I am not anywhere near your knowledge or capability. So I take my equipment to shops for repair. I never get the feeling they take the time to do all you do to match transistor characteristics, multiple capacitor test, etc. And they sure don't want replace a capacitor unless it is spewing fluid (ok, I am exaggerating there). But they won't recap a board just because it is old. I have to tell them that if they replace something one channel, replace it on the other side to make it balanced (because I learned from you than many of the old cap values are not available today). When you are trying to keep equal transients and proper imaging, that seems to be important.
Thanks Tony, I always see techs clean the PCB boards in videos but mine never come out that good because I didn't realize I had to just leave it alone after cleaning and let it self level (evaporate) Another a-ha moment with X-Ray Tony. Great video man.
Hi Tony, I really enjoy your solder and chat time. It was really enjoyable to hear a little about x-ray machines. As a first year Electrical Engineer student, I would really like to see your basic electronics videos made public. Thank you for all your effort in making these videos for us to enjoy. -Rachel
Tony, I enjoyed hearing about your work and the care you take to make sure that the details are right. 👍🏻👏
Hear, hear!
Love the solder chat and looking at it getting done. The little details teach low tech amateurs like me “how-to’s” you are probably not even aware of and consider boring. The potential future basics videos sound good too. Thx Tony, you’re inspiring.
I've had multiple x-rays, two CT scans, and an MRI, And I thank you for helping me with my health!
My friend, a little trick I use to help remove the glue without damaging the board, because I don't like seeing scrape marks on the pcb, Now, without going crazy, I heat the glue with a heat gun, trying not to heat any near by components. And if I'm really concerned about any of the components, I'll shield them with some aluminum foil or a piece of cardboard, anything to keep the heat from them. I hope this is a useful tip to others.
Really enjoy these chat and work vids, very calming. Put you on par with Bob Ross painting vids.
Thanks for sharing.
Thank you for continuing to share your repair/restoration videos! Regarding sharing the "basic electronics" videos you may make...I would selfishly vote that you share them. Stay well.
Thank you for sharing this video Tony; that Marantz amp doesn't show itself in the wild very often. I'm really looking forward to hearing the soundstage at the final checkout!
Definitely interested in your take on the basics, Thanks
Great work. I really enjoy watching your content, informative and educational but still entertaining. I'd like to see more 'solder and chat'.
Hello Mr. tony! Loving the channel. Your demeanor is very refreshing. One thing I would like to comment on is the trimming of semiconductor leads. I always solder the device first and then trim. This is to mechanically isolate the device from the cutting action to keep the shock on the lead during the cutting action from being transmitted to the device. I've seen devices fail after cutting when the lead was not previously soldered or holding the lead with pliers between the device body and the cutting tool. Just a tip from my 50 years of electronics design, test and repair. It's rare, but have seen devices outright fail or have a high infant mortality rate due to the trimming shock.
Note for the very last part of the video (cleaning the board) I always wipe off the the board after soaking it with isopropyl alcohol with Q-tips. Your method, Tony,, only dilutes the excess flux and spread it across the board and it will remain sticky after the alcohol evaporates.
I have one of these , 42 years an still working.
Looking forward to this series Tony, thanks for bringing us along!
What a wonderful looking piece of kit!
I love watching you solder 😀
Sure Tony, show the videos... the more the better :)
Another Tony-Marantz video! awesome!
I for one watch everything you put out so a refresher course never hurt no one ! I have a Microscopy (SEM) background and I remember saying "won't change much, it's the laws of Physics" oh how wrong I was !....cheers.
Thanks for video T. ,,Here benched down with: XTB-video&coffe, + schematic side by side your video. A nice weekend highlight, really enjoying listen&watch. //Have nice upcoming week.
Hi Tony, if you make some basic electronics videos I vote you make them public. We have a 13 year old girl here just starting on electronics so they would be ideal. I know you would make them informative and practical.
Sir, I really enjoy your solder-n-chats. You are very kind to share your time with us. I hope many more folks join your patreon, it’s umpteen times more enjoyable than anything on Netflix :)
Excelente Tony, este amplificador es muy parecido a mi Power Marantz Modelo 300DC, que de echo es de la misma potencia de este, bajare el Manual de servicio de este para compararlos. La etapa de potencia. La fuente es idéntica , un gran transformador con doble devanado. y 4 condensadores de 10.000uF 80V.
tiene la misma etapa de amplificacion el 1300dc con el 300dc. De Hecho el 1300dc es un 300dc + 3650 en un mismo gabinete unidos
The power amp boards are slightly different though.
@@mattfranklin3622 Si eso es correcto, me atrevo a decir que las del 1300 son mejores.
@@zambrano966 in what way?
@@mattfranklin3622 Hola Matt, bueno te puedo decir que he reparado varios 300DC y los conozco muy bien y por eso te dije eso, nunca he reparado un 1300 DC, pero baje el manual de servicio y los compare, las etapas de potencia son similares , pero no iguales, ahora si hablamos del Marantz 170DC si te puedo decir que son iguales pero con componentes de menor potencia ya que este solo da 80 vatios por canal. Para mi el circuito de la etapa de potencia del 1300DC esta mejor elaborada, pero tiene sus contras donde el 300DC es mejor. Por ejemplo el 300DC esa una fuente regulada con un transformador independiente para alimentar la parte donde esta el par diferencial Q701 (2SK109) y toda esa área en la entrada de la etapa de potencia, esto lo hicieron para que ese voltaje no se viera afectado cuando se le esta exigiendo al power, lo que hace que el voltaje decaiga bastante, en el 1300DC usan el mismo voltaje que le llega a los transistores de potencia solo lo limitan con una resistencia de 10 ohm. Ya por eso es mejor el 300DC. Pero si vemos como en el 300DC hicieron para regular la corriente de Bias, te das cuenta que en el 1300DC esta mejor realizado este circuito. En el 300DC usaron un Termistor (Q722 y Q723 SDT-100) el cual es de 1000 ohm, el cual su valor decae si la temperatura aumenta y usaron el Varistor (Q720 y Q721 MV-1) el cual también varia su voltaje de conducción de acuerdo a la temperatura, bueno te cuento si por mala suerte se dañan estos componentes no los vas a conseguir en ninguna parte, ya eso es una desventaja con respecto al 1300DC. Hay foros que dicen que en Varistor MV-1 se puede colocar un diodo 1N4148 pero este diodo no tiene el comportamiento que tiene el MV-1. En cuanto al Termistor en el mercado se consiguen termistores de esas especificación pero la velocidad de respuesta en muy lenta con respecto a los termistores que trae el 300DC. En el 1300DC usaron un transistor (Q734 2SC1568) que va acoplado a el disipador de los transistores de potencia el cual monitorea la temperatura y regula la corriente de Bias, un circuito mejor elaborado. Por otra parte en el 1300DC el transistor doble Q702 2SC2259, esta descontinuado, pero allí se pueden montar dos transistores de características semejante emparejados. Eso también ocurre en ambos power con Q701 2SK109, también esta descontinuado, pero en este caso se puede montar dos FET 2SK117 emparejados y acoplados térmicamente. Hay foros donde dicen que se puede poner el uPA68H pero no , yo lo hice y no hubo forma de ajustar el 0 voltios a la salida. Bueno espero haberme podido explicar y haberte podido ayudar. Saludos.
The main indicator of quality (and Marantz was ultimate quality) is the concrete block sized power transformers and the HUGE caps ! Talking building demolition there is enough bass out of this thing to wreck a building!
Muchas gracias 🙏☺️🎙️🎼 excelente video saludos desde México 🇲🇽
Super interesting Tony, thanks for taking us along. 2 questions: why do you cut component leads before soldering and not afterwards and is the board sticky after the isopropyl has evaporated? Thanks again!
I've often wondered in these direct coupled designs whether something could be added (a zener or crowbar or some other monitor) that would shut down a stage quickly enough to prevent such damage. I used to work on such amps etc in my dim and distant past and remember the horrors of thinking that you have found and replaced everything suspect, only for the same thing to happen again.
Excellent Job Tony! and love the story about new imaging Xrays
Excelente Tony, como siempre, Tony lao transistores 2SA968 y 2SC2238 si tienen los pines correctamente, Base, Colector y Emisor, si buscas un sustituto lo conseguirás igual, no se invertirán.
Nicer test equipment makes all the difference in testing components. Speed and efficiency.
Loved the talk about the exray. 20+ years ago I received alot of x-rays during cancer treatment and was told I was pretty neat max. X-ray exposure. Today they are not concerned and keeps prescribing more catscans etc. Now I know why they aren't concerned.
I haven't really been doing much on my bench lately because of how much everything is costing now. I'm disable and live on a very fixed income so I really just can't go on the limb to by parts to fix stuff.
Although I would love to get my hands on one of these to bring it back to life.
I would love to see your training vids.
Crazy price rises in the UK. Some of my regular stock components have gone up by 300% to 500%. Petrol and food have doubled in price.
Household energy has increased five fold and business energy by ten fold. Think our business will fold under the pressure, COVID-19 followed by huge energy and food inflation and now our customers are cutting back on orders.
When will this apocalypse end?
I loved and agreed with your comment about how many stereos do you need! I love doing the restorations, but I cant listen to them all :) time to donate and sell some off. (Its hard not to get emotionally connected to a restoration and want to keep it)
Renaissance man, much like my better half.
Yes! that would be practical, even a retired engineer in electronics such as myself would find it a good refresher. I do repair my own items and some consumer jobs, (very relaxing).
Hello tony . I am from Canada . My father was in the RCAF . He had enough rank to sign for tubes and all sorts of items destined for the dump as it was common practice to reorder to spend the years budget so the budget did not get lowered . Most are military spec. made in USA. If by chance there is something you can not source let me know and I will look in my stash . There is even single digit read outs that use filaments . North bay Ontario was the underground NORAD sight. 20 min ride in the bus to get down to the complex . Hope work slows up so you can post more vids . Have a great day EH .
Sounds very interesting to me!
Hi Tony, I have a Sony STR-6065 stereo receiver I do not use. It does work but prob needs some service being its over 40 yrs old. I want to donate it to someone who will appreciate it. Are you interested?
Interesting. I haven't seen wire wrapped connections since I was in the Navy during the 1970s.
Tony...Love your "Solder and Chats" ....They're like practial Ted Talks.........Would love to see how you teach Basic Theory.....Thanks!
Another Great Video, Thanks Tony
one thing though - I am not a fan of the amp. in my opinion it dates from after MArantz reached its peak.
it was their flagship amp , but did not have the same build quality as the US model, or the 1180 for example. fancy circuits though.
I think the quality of the PCBs and caps illustrate what I think
This amp uses the same transistor for the voltage regulator as the Pioneer SX-450 in the audio output.😛
Just a quick one, on ebay just now I've seen this model at £13,500.....cheers.
Wow that would pay my annual heating bill here in the UK. I only have a 2 bed apartment.
@@isoguy. Keep you eye's out for a bargain !
The Marantz 1300DC is almost worth its weight in gold
sir why didn't you clean the flux ? i think solder wire contain flux in it which is harmful ??
hi Tony! please make the basic electronic videos for beginners like me ! we really appreciate you patience and effort to teach!!!
So of course we must know... when you're replacing capacitors on a piece of x-ray equipment... are you minding the outside foil lead and placing it correctly?? 🤔😜
hi x-ray tony , please do make videos on basic electronics.
Jezzzz, look at that transformer!
The x-ray discussion was fascinating.
The 2330B has two varistors screwed to the heat sink that need to be released via screws. No big deal but that's the only way to get the power board to lift up after taking the module out.
Do you think the crosstalk is an important parameter overall?? Do you ever take measurements of channels separartion? Some folks - like Julian Hirsch - don't think it does not import that much, others clain that the less "polluted" channel from the other, the better, providing better soundstage, imaging and liveliness of the music.
Could you tell - in a next video - about the Crosstalk (or better channel saparation). Thank you a million.
Better than the Pioneer 1280! Look at that Transformer!
Another great, fun video, thanks. Where did you get the push type bottle for your alcohol?
I just bought one from Aliexpress for a couple of quid so thats an option.
look like someone really gave that amp a work out.
Hi Tony, you have replaced the 2sc2240 and 2sa970 with ksc1845 and ksa992. Their obvious difference is their collector current rating, ks series are rated to just 0.05mA compared to 0.1mA to the two original transistors. Do you think this is not critical?
The collector currents are 50mA and 100mA respectively (a little typo, but I understand). In some cases, this is a concern, but in this circuit, the collector current will be far below this, as they are driving the base of another transistor and are current limited by the resistors in the circuit as well as the voltage divider bias applied to the base. I am more interested in the voltage rating, as these transistors can have some pretty high voltages (as far as small signal transistors go) on them. On a side note, you will find that pretty often, this will be the case when you compare a "2S" transistor with its "KS" equivalent. This is why you always have to check. It is also why you can't always rely on those "crossover lists" that people post on the forums of electronics/audio websites. It may work for the application that the person on the forum was using it for, but not necessarily for what YOU will be using it for. Good comment!
@@xraytonyb Yo uso el KSA992 ´para sustituir el 2SA872A y el KSC1845 para sustituir al 2SC1775A, suele usarse en amplificadores Marantz de esa época, las características son las mismas.
The Atlas testers are way too expensive, it's a shame that American manufacturers don't make a similar device, it would be better and affordable.
Hi,
Could you turn on subtitles for movies, my english is not good. I use automatic translation and it helps a lot. Your movies are amazing
Greetings from Poland
I use the same component tester TC1. Did you know that this device can also check zener diodes up to 30V ? Pin 1 & 2|3 on the ZIF socket.
Like the x-ray talk, something different.
If you do basic videos, be sure to set the context, as in pose a real world issue that justifies the lesson. For instance, no one really want to learn Ohm’s Law, per se, but we might be intensely interested in learning how electricity works. Why are fuses rated as they are? Why are wires sized differently for different purposes? How does a transformer work, and why aren’t they rated in KVA and not by voltage alone? Etc. Etc.
Edit: I would be interested in your take on basic electronics . Years ago, I couldn’t find what I was looking for in books, so I took a course in the local community college which changed my life.
That is what I was thinking. Also, How do all the components work together and why, signal flow, a bit on schematics. There are plenty of videos on basic electronics on YT, and they never go beyond the basics.
I'm not that interested in basic electronic videos but one on safety would be beneficial to both beginners and "advanced". For example how to deal with high voltage, high power, xray, ... Apart from lasers, these other safety hazards are rarely discussed on youtube.
Looks like this project is going to take a while...Maybe you could explain the criteria you used to decide on the replacement transistors. I know Vce (max), Beta and Ft play a role but what other parameters do you consider ?
Yes Please !
I was under the impression that this amp was a 300DC amp with a pre amp stage added but those power amp boards are different to my 300DC.
Hi Tony, can you please let everyone know where you got the container/dispenser for your IPA? Thanks Dave
Loved the chat
to remove the glue use heat to warm up glue and will come off much easier.
Solder and Talk gives me more time to write comments. 🙂
What on earth is that second transformer at the rear? Don't see it in the manuals I find. Soft start perhaps? This unit could use one.
The smaller transformer provides power to the regulated DC power supply board. This board powers the preamp section of the amp. The big transformer only provides the unregulated power for the amplifier output section. Not sure why they felt the need to do it that way, but that's what they did. :)
@@xraytonyb Yo tengo un Marantz 300DC y es igual tiene un segundo transformador para alimentar la parte de entrada de la etapa de potencia con voltaje regulado, pero he reparado otros Power de esa época y usan la misma practica, por ejemplo el SPEC-2 y SPEC-4 de Pioneer, claro es un devanado aparte en el mismo transformador.
Hi how are ya, was just wondering if there’s any interest in a pioneer SX 1250. It’s in working order, after being on for a while the right channel fades, turn volume up a little bit and it comes back.
+1 for basic videos.
Another excellent solder and chat as well as learning session in audio electronics. Like the idea of the "led backlight" tester being used on Zener diodes. Especially for the high voltage zeners. Have the Peak, but can see the value of other tester.
next time can you please show us how to recap old model audio units? thank you.👍🙂
👍
Maybe you addressed this later in the video but at 12:46 you incorrectly identified the transistor. 2SA and B are PNP. 2SC/D are NPN
You have x-ray employees that don't know Ohm's law? In Norway I don't envision anyone without at least two years in school covering all aspects and then two years apprenticeship getting near one, besides carrying tools and boxes.
What wood working??
Checked ebay today. One going for $12,500.00 US.
Back in the late 1960's, early 70's a schematic with test points and values at each point came with receivers or communication radios..I wonder why this is not the case today ? Ha.
Where did ya get that backlight tester Tony?
What is your eBay name? I'd like to buy some of these off of you.
I guess the phono amp is quite good
This is a great series Tony I'm really enjoying it! I'm learning so much. As far as the expense of the components going up so much, all I can tell you is to vote for Trump next time...
Like an infamous Democrat said many years ago.. "It's the economy stupid!"Apparently the Democrats forgot that...
Please do not kid yourself. Not everything is polarized home politics. It is world economics. Europe is *a lot* worse off in terms of all kinds of price explosions. The cost of electricity is 500% to last year. It’s DT who ruffled up the world wide power balances with the Russians and the Chinese to begin with.
I'll tell you what if they were to make an amplifier of that quality with all those features today it would probably cost $10,000
The new Western Electric WE 91E single-ended Triode with two 300B tubes and one driver tube each, plus a single output transformer, and an integrated MM/MC phono stage is $15,000. The original WE 91A was used in movie theaters in the US starting in 1936. Reviewed in the latest issue of Stereophile (November 2022). Gorgeous amp.
Edit: The WE 91E also has Bluetooth (USB & RJ45 ports for firmware updates).
😵👍👏👏👏
I am not anywhere near your knowledge or capability. So I take my equipment to shops for repair. I never get the feeling they take the time to do all you do to match transistor characteristics, multiple capacitor test, etc. And they sure don't want replace a capacitor unless it is spewing fluid (ok, I am exaggerating there). But they won't recap a board just because it is old. I have to tell them that if they replace something one channel, replace it on the other side to make it balanced (because I learned from you than many of the old cap values are not available today). When you are trying to keep equal transients and proper imaging, that seems to be important.
Just ordered that back light tester. Amazon 36 bucks, a dam site cheaper than those Atlas testers.
Seems like it would be cheaper to DIY one out of a cheap camera flash by connecting to the flash cap with some series resistors.
9:43 - I love how easily serviceable this is, BUT the use of ''MOLEX" connectors of that size (and quality) should be limited to power-wiring!
What is your email or eBay sellers name?
Marantz overload. Too much.