Today, when I had free time, I recorded a tape and tried to play. After recording, I put the tape in the player and pressed play. The music didn't play but there was a hissing sound. The two VU needles were at maximum. The recorded tape is brought to another device and still plays normally on both channels. I tried recording the tape, the 2 VU needle still moved normally along with the music, and then I brought it to another device and it still sounded normal. Right now just playing doesn't play music, only hissing sound, and 2 VU is maxed out. So could it be a problem with the tape playback head or is there a problem with the conversion from recording to playing (meaning after releasing the rec button the machine is still in tape recording mode)? Please help me. Thank you very much.
HELP - Pioneer CT-500
- Thread starter Son Tran
- Start date
It could be that you need to clean the record bar inside the boombox. See the following thread for what the record bar looks like.
www.boomboxery.com
Record Switch Bar Example
A few boombox problems are caused by a dirty, or faulty, record switch / bar. Most of the times, the primary symptom is a high-pitched squeal when playing cassettes. Thorough cleaning with DeOxit or some other electronics cleaner will generally be the simple fix. Here is an example of what a...
www.boomboxery.com
That’s a home cassette deck Bobby, not a boombox. I’ve had one for 30 years. Been stored away for most of it. Not at all a high end deck but dang, it sure makes great recordings.
I tried hard all day but no results. These two bars are covered so I probably can't spray them inside. Opening the bottom cover of the machine, we can see the circuit board with solder joints but no gaps to be able to spray cleaning solution on these two bars. Does the two Rec and Play keys have anything to do with the mechanical part under the tape compartment? I'm not a repairman so I hope you can give me detailed instructions so I can fix it. Thank you very much.
Can the REC and PLAY buttons (mechanical parts under the tape compartment) cause errors?
You can't just spray the bars, they need to be worked. They are actually multi-pole switches that are all thrown at the same time. Yes they are covered so in order to get solvent to flow into the contacts, you usually need to stand the machine up so that one end of the bar is up, place towells under the bottom end to catch run off, and spray through the upper end. If you don't catch the solvent run-off, you probably won't be very happy, especially if the solvent runs into those meters and discolors everything, or worse. While the solvent is running through the switch, you'll need to actuate the switch 50 to 100 times. This will help to scrub off any corrosion present on the internal contacts. If the oxidation is very bad, it's often necessary to disassemble the switches to get a good cleaning, however, that is more of a last resort since it is invasive and those internal contacts are easy to misplace and damage.
You may be able to work the switch simply by moving that metal linkage. To see it in action, place a cassette tape into the well (machine off and unplugged), press record (you may need to simultaneously depress the play key to unlock the record key). As you depress the record switch, you should see the linkage lever move the record bar (technically record-playback switch). This switches the deck from play mode to record mode. There have been cases where the linkage is disconnected in which case, the machine will be stuck in one mode. However, dirty contacts will also cause this too.
You may be able to work the switch simply by moving that metal linkage. To see it in action, place a cassette tape into the well (machine off and unplugged), press record (you may need to simultaneously depress the play key to unlock the record key). As you depress the record switch, you should see the linkage lever move the record bar (technically record-playback switch). This switches the deck from play mode to record mode. There have been cases where the linkage is disconnected in which case, the machine will be stuck in one mode. However, dirty contacts will also cause this too.
I sprayed cleaning solution on the two switch bars and used my hand to move the switch many times at the same time, but it was ineffective. I will try again.
Pioneer CT-500 is very new, no rust or dirt. Is there any other cause of the error?
As I said, the bars are shrouded from the topside. Spraying them in this manner, the fluid will just run off the sides, like an umbrella. You have to do it from the ends and even then, it just seeps inside.
But in answer to your question, no, it’s not the only mode of failure. This is a lot more complicated circuit than the tape section of a typical boombox. Another concern is that these AC boxes operate at higher voltages and temperatures than boomboxes and the motors typically run continuously when powered on. Being 46, 47 years old, capacitor degradation is a real possibility. You might consider that. Also you might consider posting this question on a forum where they specialize on home tape decks, like tapeheads. I’ll just say that oxidized contacts in those big switches are the #1 reason for tape circuit issues so you should be cleaning it in any type of tape deck service.
But in answer to your question, no, it’s not the only mode of failure. This is a lot more complicated circuit than the tape section of a typical boombox. Another concern is that these AC boxes operate at higher voltages and temperatures than boomboxes and the motors typically run continuously when powered on. Being 46, 47 years old, capacitor degradation is a real possibility. You might consider that. Also you might consider posting this question on a forum where they specialize on home tape decks, like tapeheads. I’ll just say that oxidized contacts in those big switches are the #1 reason for tape circuit issues so you should be cleaning it in any type of tape deck service.
BoomboxLover48
Boomus Fidelis
I still use many of my tape decks and have over 60 various tape decks including several high-end ones like Nakamichi in my collection. Like 80% of the time the oxidation on record switches caused VU meter issues, distorted sound, bad recording and all kinds of problems.
Place the deck on a soft towel, turn the deck and leave it in inclined position leaning on a support where the record bar is facing up or down. Like Superduper said you have to do a good cleaning by spraying the cleaning/lubricating fluid from "both ends" of the bar and move it back and forth a minimum of 40 times. I would repeat more as needed.
If possible, free the tip of the record bar from the linkage and just push the ends with fingers and work it out. This way the bar gets more travel as needed for efficient cleaning. After cleaning reconnect the linkage to the record button.
Place the deck on a soft towel, turn the deck and leave it in inclined position leaning on a support where the record bar is facing up or down. Like Superduper said you have to do a good cleaning by spraying the cleaning/lubricating fluid from "both ends" of the bar and move it back and forth a minimum of 40 times. I would repeat more as needed.
If possible, free the tip of the record bar from the linkage and just push the ends with fingers and work it out. This way the bar gets more travel as needed for efficient cleaning. After cleaning reconnect the linkage to the record button.
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Today, after a while of perseverance, I adjusted the 2 switches to the correct PLAY position (the 2 VU needles are no longer at maximum) and the device plays music well. Pressing the REC + PLAY button records fine, but when STOP stops recording (release the REC + PLAY button), the device returns to the same error, pressing PLAY does not play music and the 2 VU needles go up to maximum. I had to open the machine and use my hand to move the 2 switch bars a few times, then use a dryer to dry the cleaning solution and it was OK. Thus, the 2 switching bars are dirty and not cleaned or are stuck in some position, causing an error. Now I only use it to listen to music and don't record because touching the REC button will cause an error immediately. I'm temporarily satisfied with this result, but if I want the receiver to work properly, I have to take it to a repairman.
Sounds to me like your switches aren’t fully retracting to the default park position (play). This could be due to linkage maladjustment but I suspect that it’s more likely your springs may be weak, perhaps from being stored for a long time, probably years, in the record position thereby weakening the tension.
Can you guide me on how to restore the spring of the recording and playing switch bar?
You'll just have to look at your mechanism linkage and watch what it does when you enter record mode, and then playback mode. The tape deck does not need to be on. That switch only has 2 positions (in or out). Normally in the regular (play) mode, there should be a spring that places the switches in the default position. When you enter "record" mode, the linkage usually pulls the switch (against the spring) to enter the record mode. You apparently are able to access that mode fine so there's no problem there. But when you stop the record mode, those switches should snap back to the other position. Again, there should be springs that do that. If the switch isn't going all the way back, then that's your problem.
There is either something mechanically preventing that from happening, or the spring isn't fully retracting the switch. If stretched and/or weak, you can probably find a suitable spring at your hardware store to replace it. If the linkage is bent preventing the switches from retracting all the way, then maybe bend it to correct that. Again, the deck is in your hands, this is something you'll have to figure out. You are not going to find step-by-step guidance for that exact problem on that exact same cassette deck. We can't even know for sure if the springs in that linkage is original or replaced with something that isn't a perfect fit.
The other possible issue is that your switches aren't "clean" enough because you didn't do a thorough enough cleaning. Even without solvent, it is still often possible to clean the bars by continually operating them dozens, maybe even 100 times. The mechanical friction alone has some cleaning effect, although not nearly as effective as when combined with solvent. But because you have 2 bars (1 for each channel) and because you are suffering from the same issue on both channels, the more likely scenario is that the switches aren't fully retracted.
There is either something mechanically preventing that from happening, or the spring isn't fully retracting the switch. If stretched and/or weak, you can probably find a suitable spring at your hardware store to replace it. If the linkage is bent preventing the switches from retracting all the way, then maybe bend it to correct that. Again, the deck is in your hands, this is something you'll have to figure out. You are not going to find step-by-step guidance for that exact problem on that exact same cassette deck. We can't even know for sure if the springs in that linkage is original or replaced with something that isn't a perfect fit.
The other possible issue is that your switches aren't "clean" enough because you didn't do a thorough enough cleaning. Even without solvent, it is still often possible to clean the bars by continually operating them dozens, maybe even 100 times. The mechanical friction alone has some cleaning effect, although not nearly as effective as when combined with solvent. But because you have 2 bars (1 for each channel) and because you are suffering from the same issue on both channels, the more likely scenario is that the switches aren't fully retracted.
Thank you very much. Even though it has been in production for a long time, the machine still looks new and does not show any mechanical damage. I think there is a high possibility that the switch bar is dirty or stuck. I will clean and move the switch bar from PLAY to REC in both directions several times (I have done this but less than 100 times). Hope it will work.
BoomboxLover48
Boomus Fidelis
You will be able to make it all work soon. Good luck!
Pioneer CT-500 is not a very sophisticated deck like the higher ones in that F series.
They made is so hard to work on more newer models like CT-F750, F900, F1000, F1250 etc. It is a nightmare even to replace belts and make it work.
With my limited knowledge and capabilities, I was lucky to fix all Akai cassette decks with less headache.
Pioneer CT-500 is not a very sophisticated deck like the higher ones in that F series.
They made is so hard to work on more newer models like CT-F750, F900, F1000, F1250 etc. It is a nightmare even to replace belts and make it work.
With my limited knowledge and capabilities, I was lucky to fix all Akai cassette decks with less headache.
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