@Silver965 I replaced all the four transistors (blue and red arrows indicated by your picture) the volume at FF or rewind is still louder than my other Aiwa HS. the circuit continuity is presented. Maybe IC9311 gone bad? Volume is not extremely louder but definitely louder than my other aiwa. One other Aiwa HS-PL30 has the same issue. it is still okay to play, but a minor flaw.
HI The point indicated by the black arrow when and in action the silent should be brought to zero volt from the Q11 .... the point indicated by the red arrow should be 0.6 volts more or less ... when and at stake the Q11 it does not It puts the point indicated by the black arrow en masse and you should read a positive voltage that arrives crossing R110
@Silver965 Thank you very much for this manual! I myself have been looking for a manual for this AIWA model for a very long time. Where did you find it? Greetings from Berlin, Jonas
@Silver965 you are a hero for PL50 owners. I still do not quite figure out why the FF and Rewind higher noise yet. I need to connect two leaders to measure the voltage that you indicated. I swapped most of the ICs/transistor(XK, B3, XG, RN1610/Q19) the symptoms remain the same. However, I noticed that the louder FF and Rew. noise will not increase when I turned the volume knob up. I can try to swap IC9311 which is the only IC I have not tried yet. But PL50 does have a nice and punchy sound better than my PX505. I love it. I also noticed that the Dolby B switch changes the DSL style on my unit. It is more punchy or overdrives bass when I switched Dolby B off.
A new unit is comming... I bought as non working, I think recaping its needed. The seller lives next to the sea in Spain, don't know if this cause more or less troubles with the caps, more humidity thats for sure , and hot, I think it could cause more problems, as far as I know the changes in temperature conditions are the main problems with bad caps. I hope traces are not corroded I'll let you know when it arrives,
@funbear I don't feel like a hero Just trying to help as far as I know. at this point if you continue to hear the audio, electronically, I no longer know (since you changed everything) what you can do the head when you fast forward is too close to the tape @jonas I found it on a Chinese site ... you have to register with an email User Manuals and Owners Guides - ManualMachine.com @JUAN ANDRES MONTIEL DIEZ When you get it post a couple of pics
Well, there are not very good news, I've got the unit, outside everything ok, but a hinge is broken. The sound is very loud, only one channel present, with dolby engaged, a little sreaching is audible. Tape transport very noisy. Inside, a lot of sand,corrosion over headphones solder points, and joints between main pcb and secondary buttons one
The bad news are only one channel is present, not as loud, as it should, but good quality, bbe, dsl, dolby, working ok. Mechanism runs smooth and quietly. Don't know if it's a head issue, amplifier, headphones socket, I tried with and old ones without micro that works ok. I need some kind of clue. Fortunately have the same model to compare measures. I tried to adjust gain but not any sound from left channel. Any comments will be much appreciated
The PCB looks neat, and nice and clean after your work. I like the component layout, no strange angles.
Hi, great job done so far I start from the schematic of the preamplifier on the outputs of pins 19 and 6 of the BA35313 chip you must have pre-amplified audio...to verify this you should connect an amplifier on the outputs after the resistors R9-R10 Since these two resistors are located one on one side of the circuit and the other on the other side...you will find the two left and right channels where it is marked by the two red dots...you will have audio without any adjustments...if you still have only one channel the problem could be the chip or the connections on the head .. if both work the problem is later in the diagram
Many thanks, @Silver965 for your help , I Understood I have to connect the resistors to an amplifier, but How can I do it? Soldering a wire between the resistor and a rca connexion? But It`s necessary to connect too wires ,the ground coud be connected to any ground point of the pcb?
HI these are enough for you without soldering tin anything... a small amplifier also a boombox with external input and the easiest method for those who don't have special equipment for electronics... connection to the ground .... and if you put a pin on red ... touch the contact of the resistors ... walkman in play and listen if it sounds
Hi @Silver965 , at least some time to spend with the poor hs-pl50. Test done, both channels have signal from the pre amplifier. Testing one channel and then the other one, only have one pair of crocodile conection. I could adjust the gain with the screws, for both channels, each one with their own screw. Definitively the problem is later in the diagram
let's jump ahead after the dolby chip and the BBE chip.... I would like to hear if the signal arrives in the orange square... but those components are in the internal part of the circuit... so I advise you to try on the BBE output on R44 and R43 if you have the signal... or continuing you can try on the volume input and also on its output... see colored dots on the photo
Well, What we got now, BBE out, both dot with present sound, at same level, more or less. Volume input one channel present sound, down dot on the photo, same level audible than BBE output, other channel, up dot, very loud sound, hardly audible. Output same history, only one channel runs, down dot. Amplifier in, again the same issue, down dot with sound, up dot hardly audible. In both dots sound fade away after aprox one second.
Another symptom I' ve found, when tape selector position is on metal/ cro2 engaged sound pressure level is good, however at normal position, volume level is much lower
