Yes, I've got myself lost in circuit diagrams and flux fumes. Got an Arrow "Soundtripper 3", which I bought as faulty but it seemed to work, other than some oddness with the motor. Then I recapped it.... After various oops moments, got sound both channels again, but.. The left seems brighter than the right. I'd go so far as to say it actually sounds thin. I'm 90% certain before my idiocy both channels sounded pretty much the same. I did, due to an oops, swap the amp chips over (LA4140) to make sure I'd not blown anything, and it's made no difference. Chasing circles here, trying to figure what the issue is. Don't suppose anyone can make sense of the above and say "Oh, it'll be the thingiwhatsit swibblegarb"? Edited to add: Listening again (I'm using speakers, makes it a bit harder), it's like one side's too bright, one side too muddy, and through speakers the two channels together sound perfect.
It's over my experience so I can't help you electronically but can you post a photo of the player and maybe the test setup? I'm not familar with Arrow Players and would love to see it.
I'm doing it for a vid, so I'll try to grab some stills Will also scan the schematic, in case it's helpful for anyone else messing with one of these. I had a brainwave, after doing another cap replace in case I'd somehow made a mistake first time around... I figured I'd hook the output from the preamp into a line in to my speakers... I don't quite believe where I'm going with this... The left channel from the preamp sounded nice and clean through the left speaker. The right channel from the preamp sounded muddy through the right speaker. ... Can you guess what happened when I tried the left output on the right speaker, and the right output on the left speaker? Yeah. I think my next repair attempt is to try to get my speakers both sounding the same...
Nope, it's to fix this again. I went to solder the mic wires back on, and unsolder one of the volume control wires to heatshrink where the insulation was damaged, and... Have spent the last x hours trying to deduce quite what went horribly wrong. I think it's the soldering iron - Fairly sure it's not normal to get a tingle when holding solder wick in one hand hand momentarily grounding against the chassis with the other. I'd accidentally left the adapter and line in connected (although powered off), and I think the damned soldering iron sent a current where a current shouldn't be sent. Result is a lot of motor interference, almost no audio unless sliders up to max, and general nastiness and need for wine. Parts on order...
It makes sort of the right sound again! Don't ask me how, and I wasn't pointing the camcorder at the whole process, but an amp chip swap and replacing every single capacitor on the left channel seems to have done the job. Amp chip alone didn't. Caps all the right way round. Shrug. Mic's now dead though. But as the soldering iron unexpected discharge moment happened soldering it back on, that's not a huge surprise. Guessing the current went through the mic, through at the very least the left amp, and through probably me after. Really want this done and back together, not sure whether to try the same diameter but deeper mic from a Philips boombox I've slightly killed, or just feebay a new one and pretend to wait patiently.
So, these microphone things.. .They're not all the same then. New mic in, feedback at anything above barely any volume. A search suggests the sensitivity can be dropped with a resistor change, so that's tomorrow's job.
Was tempted to ask this as a new thread, but as it relates to this damned thing (which is no longer cosmetically perfect - Warning, don't let slightly moist with iso tissue anywhere near the case of an Arrow Soundtripper 3...) I'll drop it in here... Combined amp/ pre-amp chips - The amp on this was allegedly 0.5W, which I guess is necessary for the twin headphone sockets. How do I go about finding combined amp/ pre-amp chips of similar rating?
Most personal stereo amps range from 5mW to 30mW RMS per channel into 32 Ohms. 0.5W will be at the maximum rail voltage and the lowest load impedance. If it's the LA4140 you're looking for, I just found them for sale on eBay, item number: 292857326894. Good luck
