Hi everyone , my JVC BR-S611U professional SVHS vcr vu meters don’t register signal when I try to record audio from XLR line puts otherwise it does record and playback the the audio very well . The strange thing is when mic inputs on front panel are used you can see the vu meters moving and you can hear the audio from the built in headphone amplier in both left and right channels also you can see the vu meters moving when you play back the recording you just made from mic inputs and audio from headphone amp as well the audio from line output through a external pre amp but when you try to record from audio from line inputs the signal dies not reach the vu meters and no audio is heard from the headphone amp and as mentioned above apart from this you can still record and playback the audio . What might be causing the problem ? I have the service manual for it . I purchased it used . It’s in very good condition the sound and video quality is the best I have ever seen from a vcr and this things weighs 50lbs 🙂 any kind help to trouble shoot this problem of why the audio signal is not reaching the vu meters and built in headphone amp when line inputs are used will be greatly appreciated! Thanks 🙏
I suspect no quick and easy answers to this one. If its purely a VU meter issue on record from line input only (along with no headphone output under that condition) then the only logical course of action is to start at the VU meter or headphone amp and work back using a scope to trace the signal.
Its a very complex bit of kit yet curious in having analogue meters... which may work in your favour faultfinding. You have one good channel to compare against but key to this is tracing the signal. I wouldn't like to speculate, its an odd fault and could easily be something physical rather than a component failure.
Its a very complex bit of kit yet curious in having analogue meters... which may work in your favour faultfinding. You have one good channel to compare against but key to this is tracing the signal. I wouldn't like to speculate, its an odd fault and could easily be something physical rather than a component failure.
Hi , thanks for your kind d reply I have enclosed pics of the schematic of the vu meters circuit also what the vcr looks like! Maybe looking the schematics it can tell you where the problem might be , thanks
Believe me, its not that easy... you are going to have to do some very methodical signal tracing.
You say headphones and meter are affected and so that suggests the problem is before these points which are common to both, however you need to check and confirm the signal really is missing at one of these points and is to look further forward in the circuit.
Do you have a scope?
Hi Mooly, I do not have a scope can I trace the problem with fluke 189 true rms digital meter that you see in pic . There is Toshiba 4066 bilateral switch in the circuit pass the mic/line sw TK 10521 ic switches , I unsoldered all the TK 15021 switches all tested on , I might have a new 4066 bilateral ic switch it look like the signals is routed through this switch as well do you think if it’s gone bad it might effect the line audio reaching the vu meters but still passing the mic audio to the vu meters ?
Correction TK15021 ic switch there are 3 of them all seem ok tested out of the circuit with the fluke 189 digital meter at diode settting
A scope is essential for tracing signals. The problems could be any of a hundred possibilities.
You can try with a meter but the only hope would be to apply high level constant tone inputs (440 or 1kHz sine) to both inputs and trace the signal that way. You would only be able to compare left vs right but you might get lucky and find where it is disappearing.
Removing and changing parts in hope isn't going to fix this one.
You can try with a meter but the only hope would be to apply high level constant tone inputs (440 or 1kHz sine) to both inputs and trace the signal that way. You would only be able to compare left vs right but you might get lucky and find where it is disappearing.
Removing and changing parts in hope isn't going to fix this one.
Wow! Mooly you are an expert technician I can see that ! I agree with you it might be complex problem . Have you ever encountered a problem like this and what was the reason in the case. From your experience from that problem what do you think might have occured to cause this problem , the vcr look close to new inside look , I know people some time don’t pay attention connection the wrong cables to inputs and outputs resulting in overload making a component inside short . I truly appreciate your help in trouble shooting the problem you are more experienced than I am . I have couple of scope by I don’t know how to use them , maybe you can help ? Thanks as always !🙏😊👍
To even begin this you would have to post the full service manual so we can see all the circuitry, and it needs to be a proper manual that is clear to read.
It really could be anything at this point. You even have to be certain you have it configured correctly (all the user controls and level pots etc). Beyond that it is tracing a known good signal from the inputs and seeing where any problem might be.
Hi Mooly, the service manual and Instruction manual are available online for free from nice folks at internet archive if you type in our browser” JVC BR-S611U vcr service “ you will see it there . There are so many pages it will take forever to post it here . Yes you it might be something simple one thing I like to mention I had to make 4 custom xlr to rca single ended cables and use a adapter to connect to 1/4”stereo headphone output jack of my apple ipad streaming music from online you tube music to the vcr left right XLR audio input . The XLR is a 3 pin balanced audio connector to connect to a single ended rca connector you have to connect the two pins in the XLR together leaving pin 2 as signal carrying pin. Do you think connecting the two pins of the XLR audio in might some how have grounded the signal to the vu meters?
You are going to have to do the legwork on this one 🙂
I did spend a bit of time looking yesterday for a good pdf manual and turned nothing up. If you have the manual post it here or if its to big put it on Dropbox etc
I did spend a bit of time looking yesterday for a good pdf manual and turned nothing up. If you have the manual post it here or if its to big put it on Dropbox etc
Hi Molly, bracing for a major snow storm to hit wash dc and many states up east coast have to put this venture on hold for for 3-4 days . Will you be okay with the pages that relate to the audio section of the JVC BR-S611U vcr I am really suprised that you were not able to download the service manual because I had no problem when I typed JVC BR-S611U VCR FREE SERVICE MANUAL one of the site called Internet archive have this manual for free download that is where I got mine plus they have many more manuals for many more products all they ask the users if they can us to make a small donation so they can continue their good work if possible . Another that came to mind was the when you play audio from a commercially recorded vhs tape line hi fi stereo Dolby recorded sound from Star Trek movie that you see in one of the pic again the audio can be heard beautifully in stereo but the vu meters on the front panel do not move nor is audio heard from the headphone . The only instance they move before , during recording and during playing is when audio is recorded from mic inputs . There is board on this VCR called SERVO I AND SYSCOM there are various micro selectable switches that con be configured according to the user need When the vcr was shipped from factory new JVC engineers adjusted these switches to standard factory setting which most user would use . There is a possibilty the pro studio who used thus vcr before me changed the factory setting to the ones that met their needs one of that might have been to defeat the vu meters or control them from an external edition the JVC made both for this model and higher up BR-S811U. Can you please try one more time to get the service manual from the site I mentioned above . If you still can’t please let me know if you see how many pages this service manual is your will understand very well written and covers everything ! Many thanks ! Ali
Nothing is coming up for a manual. To stand any chance I really need a full manual that should show block diagrams and configuration settings as well as the circuitry. It needs to be clear, as clear as this to trace and make sense of things and you also have to be happy working identifying and probing such circuitry with a scope.
This is why a full manual is needed. It is very unusual to have switches like this internal to a product and we have no way of knowing what anything does without the manual.
It would not surprise me if this 'fault' wasn't some configuration or user setting. We just don't know for sure though.
So that is one known state where it does not behave as you expect and that gives you something to work with. You need to find where the VU/Headphone feed is picked off from the audio. It may be a fault or it may be a configuration setting.
There are no guarantees but without a full manual its really a non starter I'm afraid. You should also try and get a full user manual if possible as well.
This is why a full manual is needed. It is very unusual to have switches like this internal to a product and we have no way of knowing what anything does without the manual.
It would not surprise me if this 'fault' wasn't some configuration or user setting. We just don't know for sure though.
So that is one known state where it does not behave as you expect and that gives you something to work with. You need to find where the VU/Headphone feed is picked off from the audio. It may be a fault or it may be a configuration setting.
There are no guarantees but without a full manual its really a non starter I'm afraid. You should also try and get a full user manual if possible as well.
The only one I can find is BRS611E
I'm spending far to long chasing this 🙂
You'll have to upload the pdf manual and it will have to be clear and readable.
I'm spending far to long chasing this 🙂
You'll have to upload the pdf manual and it will have to be clear and readable.
Hi moooly the BR-S611E is the same except the E means it’s had European PAL color system the U version I have is USA version hence the U with NTSC color system otherwise they are exact same machines . Thanks hope you will be able to track down the mystery of the missing vu meter and headphone audio from line inputs . As always you kind help is very much appreciated ! With best regards! Ali