When I send my brother a cassette tape I’ve recorded, he says it is blank. Is there any way to overcome this?
Along the same line, I once taped a show and then tried viewing it on a different TV set. It was wavy. Is it possible to overcome this?
Possible if record/playback head alignment between units is way, way off. Short of using very expensive deck with head auto azimuth alignment feature there is nothing you can do short of trying another deck and hoping for better luck.
couple of questions for you
are we talking audio cassettes here ?
Does your machine record and play back its own tapes fine?
Did you check the tape before you sent it off ?
Does your brothers machine play back pre-recorded stuff ok?
As for the video recorder one, it looks like the tuning on the tv is slightly off, maybe if you put the video test signal on, and retuned the tv, things would improve.
Yes, my recorded tapes play back just fine. I use Sony and Maxell tapes for recording.
Yes, I listen to the tape before sending it, and my brother’s player works just fine also.
Is there another brand that might do better?
Did you tell him to press ‘play’ and not ‘record’? 
I’ve never heard of a failure of this kind. It’s pretty straightforward electromagnetic stuff going on - so If you can hear the tape you made when you play it back and he can hear tapes that Columbia/Warner/Sony/MCA/Virgin (how many are left, again?) made, then I can’t think of anything that would give him the impression of a BLANK tape except human error, or a GROSS discrepancy in your record/playback level and his volume knob and hearing ability.
Since you (him, too?) can hear commercial tapes the head alignment should be fine. And it’s unlikely that it is off far enough to hear nothing. Too far one way and he would hear the other side of the tape backwards. Too far the other way and he would lose a channel. The adjustment screw on all decks has travel too short to get much more, if that much. If the screw is completely out, he might.
I’m going with pilot error. Not you, but him. Or a BF magnet at the post office.
Did you use a different VCR? If you did the lines are almost always a tracking problem.
You can usually manually adjust the tracking on any VCR.
So then, we know your machine records and plays back fine and your brothers is ok, on top of that, the tape you sent played back to you ok.
The information on the tape was there to start off with so it must have disappeared either in the post, unlikely but possible I guess, or your brothers machine has erased it as he was trying to play it back.
The only way you can satisfy yourself completely is to take another tape you recorded on your machine and put it into your brothers machines yourself.
If it is blanked out again then his machine has to be faulty, but if it plays fine then maybe the mail service stuck your tape under a scanner. This can certainly damage the recorded information but I would be surprised if it erased it compltely.