Another tape loading aid, ZX81. Measuring 119 x 99 x 40 mm, the box has a small edgewise meter set into the front, and a three position switch for Load, Off and Save. There's an LED to indicate when the switch is in the load position, which of course means that you require a battery, a PP3 in fact.
The instructions are clear and easy to follow, and on the back page are four illustrations of the screen showing various load signals.
To test the unit I used an old cassette recorder/player that I had proved was no use for computing, then I found some old tapes which I had labelled as 'unloadable'. After setting up as per instructions, every tape loaded perfectly and re-saved perfectly to become quite normal tapes again.
It can be left in position all the time, which saves you the trouble of moving leads (to avoid the ear/mic loop). The battery retaining clip is not very effective, but to be fair, you wouldn't be throwing the thing about (would you?). A bit on the expensive side, perhaps. A Spectrum version is also available.