"Pinch Hits" & "Switch Hits" – The Cassette Gazette Page 6

written by Matthew Reed

The Cassette Gazette was a 1983 one issue advertising newsletter that was a joint production of Lemons Tech and KWIK Software. The Gazette described the products sold by the two companies, mixed in with operational advice and interesting facts about using cassettes with your TRS-80. It appears to have been written by Wayne Lemons, the founder of Lemons Tech. The Gazette is reproduced here page by page with permission from Wayne Lemons' family.

“Pinch Hits” & “Switch Hits”

When a program tape develops a fault it is usually called a “hit.” One common type is a “switch hit,” which is a sharp spike of noise placed on the tape when the motor current stops suddenly. If you switch off your recorder in the middle of a program, or if the program bombs and the computer turns the recorder off, any switch hit that occurs will make that copy forever unloadable. A capacitor or diode or both across the CTR motor can help this problem… but we, of course, think we offer a better solution.

The SOFTROL is a solid state switch that has a built-in one-second motor off delay. The power to the motor is reduced slowly to bring it to a “soft” stop, instead of cutting it off abruptly.

But the motor off delay does more than just stop switch hits… the extra one seconds pulls the tape nearly two inches beyond the point where the recorder gets the signal that the program is through. This pulls the end of the program out from between the pinch roller and capstan of the recorder. Without this action (unless you always remember to release the recorder PLAY button), the end of the program is being squeezed continuously. This can put a dimple on the tape that busts the load… a pinch hit… just before the end of the program.

Out SOFTROL eliminated both “pinch” and “switch” hits. But even more, it provides pushbutton control of the CTR motor in both PLAY and RECORD modes so you can position the tape, puts gaps between programs, etc. The one-seconds motor-off delay also automatically puts a silent gap between program you save… just in case you forget to do so; this gap makes it a lot easier to find where each program begins on the tape.

This soft switching action greatly reduces the current handled by the CPU relay, and virtually eliminates arcing of the relay contacts. This is very significant on the Model I, particularly if many ‘data' tapes are recorded or loaded.

Open Ground Problem

If the shield of either the EAR (black) or the AUX (white) cable from the TRS-80 computer breaks, it will cause a lower signal output from a CTR-80. (Technically, this is because the EAR jack floats above ground by 33 ohms, while the AUX jack returns to ground. When both the EAR and AUX jacks are plugged in the 33 ohm resistor is normally shorted out so that you have maximum recorder output. But if that shield is broken, the 33 ohm resistor remains in series with the EAR signal, lowering the output.)

When not using a loader, this problem may result only in having to turn the volume higher to get a load. But if the trouble is intermittent (comes and goes) you may find it almost impossible to load a tape.

When using a signal-active loader, however, this condition can reduce the signal to the point that weak tapes will not load reliably. With a powered loader, such as the BPL or LPL, it makes little difference whether the shield is connected or not and loads may be normal even if the trouble is intermittent.

To check your cable: while listening to a program through the loader monitor, simply pull the AUX plug from the recorder; the signal level should decrease. If it does NOT decrease, you have a broken shield. To check for an intermittent connection, leave the AUX plug in and move the cable around, bending it here and there. If this causes changes in the signal level, there is a break somewhere. We don’t recommend repairing a worn cable… get a new one from R/S.

New LemonAid Loader

What beats a LemonAid? Nothing until now. Lemons Tech announces the PLUM, a new battery powered loader. Unlike the signal-powered LemonAids, the PLUM does not require modifications to non-CTR80/80A recorders. It works with the CTR40, 41, 43, 80, 80A, CCR81 and other recorders without wiring changes, and is compatible with TRS-80 Model I/III low, high, and KWIK baud rates as well as Timex/Sinclairs. It plugs between the EAR jack or the CTR and the computer in seconds… the same as a LemonAid.

In addition the PLUM has automatic on-off, using power only when it ‘hears' a cassette signal, meaning that the low-cost internal battery will generally last a year or more. But that’s not all. You can use it to make CTR to CTR program copies, either single or multiple, including low, high, and KWIK baud rates. Use this feature, for example, to make single backup copies of your tapes, or for making multiple commercial copies using several slave recorders. And there is a built-in audio monitor for locating program starts and ends, and keeping tabs on “what’s happening” during saves or loads, or when making copies.

The new PLUM is suggested whenever you want the best loader you can buy… one that can even rescue ‘unloadable' tapes. It is especially important if you have other than a CTR80 or 80A, and don’t wish to make modifications to your recorder. For example, the new R/S CCR81 should be modified for best results with a regular LemonAid, but not if you use a PLUM.

Want to upgrade from a LemonAid to the new PLUM? Call Lemons Tech for trade-in information.

CTR As ‘Game Monitor'

Own a CTR41, CTR80, CTR80A, or CCR81? On request with any order, we will send you a modification sheet showing you how to make a simple modification (you solder in one resistor) so the CTR will monitor program-generated sound. The resistor and an easy-to-follow drawing comes too. If you don’t want to order anything right now and would like to have this “arcade” sound modification with part… send SASE and $1.00 to Lemons Tech.


Get your order quick… give us a call (9 to 9 except Sunday) and you order will be on the way in 48 hours or less (usually less… we try for the same day). Order hardware or software or both with only one call to either company. If you get a busy signal or a non-answer, call the other company. Use MC or VISA… C.O.D. is $3 extra.

We promise satisfaction or your money back. Just return the undamaged product with a short note telling us why you are not satisfied… that’s it.


We are confident that no damages can occur to your equipment due to the use of our equipment, programs, or suggestions. Nonetheless, we assume no responsibility for any damage or loss or alleged damage or loss directly or indirectly due to the use or misuse of our products or suggestions

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Categories: Cassette Gazette