This is the fourth article we have had on this subject. We still receive many calls and letters about various SAVE/LOAD problems.
One of the most common is that an individual orders a tape from an outside source, whether it be us or some other Software House, and can’t load it into the computer. The identical phrase is used by almost all of these people:
“This tape won’t load at all. None of the programs on either side can be loaded into the computer. I know it’s not my tape recorder because I can save and load programs I entered myself and they work just fine”.
Well, I have discovered that, in many cases, it is the tape recorder that is the culprit. “How can this be”, you say?
Simple; the RECORDING HEAD IS OUT OF ALIGNMENT. The head is saving the program off-track and when it is re-loaded it is re-loaded off-track. Programs that are saved with professional recording equipment record the pulse in proper track alignment – – – most of the time.
This problem of the head being out of alignment is a lot more common than I thought. Sometimes it can be corrected by an adjustment, as outlined in the owner’s manual. On the CTR recorders that I have, there is no adjustment that I am aware of and I have to take the recorders to a service center.
We personally use the DIGITALIZER equipment (see this month’s EDITOR RAMBLINGS) along with the new Radio Shack CTR-81 recorders.
If you feel your recorder might be recording off-track, use another recorder (borrow a friend’s if necessary). Try loading programs you made yourself and then the commercially prepared programs.
If you are in the market for a new recorder, I recommend either the General Electric 3-5158 Computer Tape recorder (51.95 retail, usually cheaper) or any of the Radio Shack CTR computer recorders (CTR-41 – 49.95, CTR-80 – 59.95, CTR-80A – 59.95, CTR-81 – 59.95, the CTR-81 is their current model).
For a real bargin, contact your Radio Shack Computer Center and ask them if they have any rebuilt CTR computer recorders. You can usually get them for about half price but many of the smaller population center areas may not have any available.
However, if the problem cause isn’t the recorder, disconnect the EAR plug from the recorder jack and listen to the program pulses. Try to hear any of the following:
– DROPOUTS – these are sudden drops in volume that can cause the program to bomb, the result usually being the return of the <K> cursor. They may be caused by the tape becoming stretched. If there is a lack of magnetic particles in any part of the tape, dropouts can occur. Demagnetizing the tape with a bulk eraser before recording on it can sometimes help. Dropouts can somtimes be overcome by increasing the volume adjustment of the recorder. A trick I have used, that sometimes works, is to locate the dropout location by noting the position of the number counter. I load the tape again and when the tape approaches that position, I increase the volume on the recorder and then decrease it when that position is safely passed. – WAVERING – this is the effect where the volume of the sound pulse pattern keeps cycling from high to low in a constant manner. At the high point, the program might blow. At the low point, data may be lost to the computer. Volume adjustment sometimes overcomes this effect but in extreme cases, nothing helps except if a device, such as the Winky Board (G. Russell Electonics – BULLETIN BOARD on cassette this month), is used. This problem is caused by either a bad recorder or a bad tape. – DISTORTION – extra noise on the tape interferes with the computer’s ability to identify the program pulses. This may be leftover strong pulses if the program was recorded over an old program. Again, de-magnetizing or a device like the Winky Board can help. – UNEVEN PULSE RATES – this can usually be traced to a problem with the recorder’s drive mechanism. The belts may be slipping or the motor may be binding. Consult the recorder manual for proper lubrication and cleaning procedures. If belts receive a coating of lubricant, all sorts of problems can arise. Belts can enlarge as they get old and may have to be replaced. Sometimes they just keep falling off the drive wheels. – EXTREMELY HIGH VOLUME – the result of this is usually the screen going blank with no cursor. This is usually easy to remedy just by turning down the volume except if there is some other kind of distortion, also.
Sometimes, the head of the recorder itself becomes magnetized or dirty. It is usually a simple procedure to clean or demagnetize the recorder head. Most vendors of cassette recorders sell tape cleaning & demagnetizing devices.
* If you have trouble SAVEing programs, I might suggest:
– MAKE SURE THE PROGRAM IS NEVER SAVED AT THE BEGINNING OF THE TAPE. You have no idea how many times people have tried to save a program before advancing the tape beyond the leader. All tapes (except leaderless tapes) have a segment at the beginning and end of the tape made of a plastic material that have no magnetic particles in it. These segments are designed to affix the magnetic tape to the two spools. They cannot hold and data themselves. – disconnect the plug from the recorder EAR jack while recording. The recorder may pick up unwanted noise from the computer through this circuit. – use quality cassettes. They don’t have to be expensive and some expensive tapes are less suited for storing computer frequency pulses. – run the recorder on batteries instead of AC. The AC power source into the recorder may introduce voltage spikes or hum that shows up as distortion in the recorded program pulses. Some recorders may have a problem keeping the drive motor operating at a constant RPM when on DC current, so make sure the batteries are fresh. – find out if there is an extreme amount of noise that accompanies the program when the RAMpack is attached and a program is saved, as compared to saving a program with the RAMpack un-attached. If there is more noise, consider obtaining another RAMpack. Our experience has shown the Memotech RAMpack to be less noise-producing than most. – in extreme cases, run the computer on batteries when saving a program. This involves building a power supply with batteries. Make sure that proper polarity is observed. The power plug tip should be positive that comes from the battery pack and goes into the computer. IMPROPER POLARITY CAN CAUSE DAMAGE TO THE COMPUTER. If you have any doubts, ask someone who has some expertise in this area. I built such a device with NiCad rechargeable batteries inside of a metal case with an input jack for the computer’s power supply which is used to charge the batteries – on/off switch, output plug on a 2-wire cord for the computer and DC meter to check the power status of the batteries. The whole thing cost me less than $30.00 and I bought all the parts from Radio Shack. Another alternative to the battery pack is a filtered power supply for the computer 9VDC power supply. Radio Shack (I’m beginning to sound like a commercial) sells one – part #15-1110 for 6.95.
* If you have trouble LOADing programs:
- disconnect the plug from the recorder MIC jack while loading.
- if the recorder has a treble/bass adjustment, the treble should be at maximum level and bass at minimum.
- if the recorder has a high/low switch it should be at high.
- the volume adjustment, if set at 75% maximum, is usually the best setting.
- run the recorder on batteries.
I don’t suggest you try all these things at once but one at a time until whatever problem you have is overcome.
PROPER VOLUME SETTING ON RECORDER.
One method I have found for getting the proper volume setting for any 16K program which I wrote about in our July/82 issue. I will review it again here because it bears repeating. Put a 16K program (use one, if you have it, that doesn’t have any data recorded in it, such as a file or word-processing program) into the recorder and follow the following steps:
A. type in LOAD “XXX” but don’t ENTER it yet.
B. turn the volume of the TV up so that you can hear the audio pulses of the tape.
C. press ENTER on the computer.
D. press PLAY on the recorder.
E. let the program feed into the computer until you can hear the even-sounding pulses. It should occur at the end of the program and have 24 pulses that last 17 seconds.
F. if you have a tape counter, note the location where these pulses begin and end. You are going to have to probably return to this segment a few times with the recorder’s FAST FORWARD and REWIND keys. Do not worry about the program bombing while you are stopping, rewinding and restarting the recorder. The computer is searching in vain for the program “XXX” and will not bomb.
G. when you are comfortable with finding the locations of the pulses, advance the tape to the point where the pulses begin. There should be 5 horizontal bars that are relatively steady. This situation will only last for 17 seconds. Before these pulses, the bars did a lot of jumping around. You are now going to adjust these bars so that the edges have very stright and clean edges.
H. start turning the volume up on the recorder until the bars start getting fuzzy edges. If you turn the volume too high, the bars may get wider and wider until there’s very little white left on the screen. When the fuzzy edges occur, stop and turn the volume down again until the edges become crisp and straight again.
I. make a notation, on the cassette case itself, of the volume level for future reference.
J. at this point, the volume level is set as good as it can be. Hit the BREAK key, rewind the tape and reload it in the normal fashion. The program should now load OK unless other problems such as dropouts, distortion or wavering exist.
The computer itself can be a source of problems, particularly the earlier kit models. Weak solder joints by the builder were a common cause of erratic performance.
Good luck!