I mentioned this in the Tech Chat forum, but this seemed the place to introduce a new project. Issues found so far are: Tape deck not working but is making sounds like the motor is running. Belts on the way. In stereo mode on FM, there seemed only to be sound from the left channel. On playing with the balance knob there is now sound albeit at a reduced level. Sound from both sides on mono. FM stereo indicator light doesn’t. No light for the radio tuning dial. Not 100% certain that it has one, but it looks like it should. I’ve tried a 5pin Din to 3.5 jack cable attached to an Echo Input, but not having any success yet. Any ideas on how that might work would be appreciated. Pin layout on the cable is (I think!) 2 ground, 3 left ch+, 5 right ch+. Unfortunately I don’t have a cassette at hand to try rec+play/pause, it might be as simple as that. The RIF switch next to the Din input is stuck solidly on the “A” position Pics attached
A wee bit more fiddling! The aerial seems like it could be better earthed. FM sounds lovely, even in mono, but when playing about trying to get stereo channels I realised it was better when I held the antenna… I got hold of a cassette and can confirm that record and pause isn’t helping with the lack of line in from the Din plug. It may be the cable is wired wrongly for the box I guess, but I’m also currently clueless as to any switching etc. that I may need to set correctly. I have also hit two local pharmacists on my way home in the hope of picking up some isopropyl alcohol - but to no avail… I may have to speak to Amazon!
In regards to: "The RIF switch next to the Din input is stuck solidly on the “A” position" I can offer that it could be oxidation of the switch contacts alone that is responsible. I had a 1978 Hitachi clock radio dumpster find over the last summer - all slide switches were extremely difficult to move with one of them all but seized. Deoxit from inside on each switch + cleaning the plastic slide part + Teflon grease (Labelle 106) to the side of the plastic to plastic contact area solved the issue nicely. Switch may be the same type of issue. Question: Does the MW (Medium Wave in Europe = AM in North America for those reading) radio work? If so does audio come from both sides? Deoxit is expensive and can be, to some extent, replaced with 99% ISP (alcohol from pharmacy) as a stop gap temporary measure. I used that as a substitute before I finally paid about $40 for a can of the Deoxit from amazon. The Balance knob may benefit from a drop of either, applied from inside the cabinet, directly to the pot wiper tracks. The side of most potentiometers have a hole or slot through which one can glimpse part of the moving inside conductive surfaces. Deoxit or alcohol there and let sit. Though, with all old boombox finds, a thorough Deoxit to every slide switch and pot is almost mandatory to avoid frustration. Especially to those internal slide switches on the circuit board that move when Radio / Tape selector are moved (in most models anyway) or when Play or Record are pressed.
Spent an hour or so inside the box today! The main drive belt was goo, the capstan drive was sticky and slack and the tape counter remarkably good for its 45yrs! I replaced all three and gave all switches and pots a good cleaning. The only concern I had (as a newbie to all this) was the goo in the attached pic. It looks possibly to be some sort of sealing wax? I think that’s a black screw head that has been revealed on top. I would happily be corrected though. Stereo sound is back and the cassette deck is playing, fast-forwarding and rewinding. Sound quality from the tuner is great - a real surprise. However, despite cleaning the filthy pinch roller & capstan and the head (which didn’t seem nearly as dirty) the sound is pretty rubbish. Dull, quieter than the radio and not much response to the tone controls (bass & treble knobs make a very discernible difference to the radio). I’ve only got one tape here just now, so it may just be that my Emerson, Lake & Palmer recording hasn’t aged well… Just remembered, the grain of wheat bulb for the “Stereo FM” indicator looks pretty blackened. It has a sheath around the sides so hard to get a good look and today was more about trying to get the cassette side of things running anyway. I couldn’t see a bulb holder for the VU meter and the radio dial face is hidden behind the tape mechanism. I’ll need to ask whoever it was that did one of these previously if theirs lights up.
The goo is wax used to hold the fine radio coil wires. Looks like it may have melted somewhat. Grain of wheat bulb needs replacing if it is blackened. Try a different tape later it may be better. FM especially is always at least twice as loud as the cassettes I record and play back, at least on the few old boxes I have. Might just be that or pots and switches need deoxit also.
As per the Tech Chat forum, I now have a working line-in (and probably line-out…)!! Not using the absolute best of quality leads etc. but they’ve proved the theory and got a 21st Century source connected to the 47yr old ‘box. I’m happy enough at that for the moment, but it has highlighted the poorer sound quality from the tape deck side of things. I’m going to have to knock out a couple of fresh tape recordings to see if it’s simply old cassettes that haven’t aged well that is my issue or whether there is some adjustment that can be made to improve things. Tapes tried so far that I can rely on having been decent recordings in the mid to late ‘80s are on TDK AD90s and SF90s plus three pre-recorded finds. Quo’s 1982 album sounds dull, a Stone Roses album and Leftfield’s Leftism sound better but are obviously significant newer purchases. They also seemed to start to sound clearer after playing for a couple of (top!) tunes. I have cleaned the heads etc. with rubbing alcohol… Is there much to be said for trying recording and playing back on the box itself? If such recordings were sounding better than recordings from other sources, does this suggest that the heads on the Hitachi could be realigned or otherwise adjusted to improve performance? What about the fact that the modern line-in source sounded good - whilst, I assume, running through the deck’s recording side to the amp section? Would that suggest an issue with the playback side of things? Time to have a play about with fresh recordings I guess…
I love that model but they don't show up around here as much. As far as the DeOxit, the guitar stores usually have it for the best price and largest containers, at least over here.
Hitachi trk-5280h did I ever service this one? I can't remember. Did I ever mention I have one with the original Styrofoam. I'll just say I had to move a bunch of things out of the way to get to it here. Let me show you what I'm talking about. Can you still see it at smack dab in the center of this picture.
My Hitachi is still playing away fine. I haven’t felt the need to do much further work on it! The level meter light bulb still needs replacement but I was deliberating between a bulb or LED and if LED should I also try lighting the tuner dial too. The only other thing I’m considering is building in ‘Alexa’. I’m currently running an Echo Input through the ‘box, so thinking it might be a nice project to fit it internally - and that it might also moderate my wife’s feelings towards the “hunk of junk”
