Dear Editor,
Enclosed is my renewal for two years. I enjoy SyncWare News even though some of it is over my head. I started out with a ZX-81 four years ago. I bought a TS 2068 two and a half years ago. I have used the 2068 until the “Caps Shift” keys are just about unreadable. Please remember that all of your subscribers are not computer wizards but we do enjoy working with them.
I have a Tasman I/F and use an Epson LX-80 printer. Before I found David Ridge’s TASMAN+QUADRA CHART fix in SWN 2:6 I could not figure out how to dump the screen to the printer. I use CURVE TRACING-2068 from SWN 3:2 for simple wiring diagrams. I am now trying to figure out how to add letters and numbers to the TRACING. To me the above two programs payed for my subscription to SyncWare News. Keep up the good work. Just remember those of us that have picked up on computing by sitting down at the keyboard and enjoying the art as we learn.
Les McCullough
Amarillo, TX
Dear Les,
Thank you for your encouraging letter. I’m glad you enjoy our magazine. The fact that some of it is “over your head” is good to hear in a way. That means we’re presenting challenging material with enough “meat” to keep it from being boring. However, we’re also aware that not all of our readers are “computer wizards”. In the future we’re going to try to include more articles geared to those just getting started with the technical aspects of the TS computers or are not heavily involved in hardware hacking. Our goal has been and will continue to be bringing you the best TS technical magazine on the market.-jm
Ddear Editor,
A few days ago I bought a color TV set with a composite video input on it. Now when I use it with my TS 2068 (computer monitor output to composite input on TV, TV in video mode), there is distortion taking place on the screen when I use some BORDER or PAPER colors. White PAPER with a black or blue BORDER results in the vertical edge of the PAPER to be wavey of distorted. The same applies when a white BORDER is used with black or blue PAPER but is not as severe. Let me know if you have any suggestions to correct these problems.
Another problem occurs if I want to PRINT say a bunch of squares in blue INK on a yellow PAPER. The squares appear to be black. There is also a “shadow” phenomena, ie. if I PRINT squares in green INK on yellow PAPER. A yellow shadow will appear at the square’s left edge and a brown shadow will appear at it’s right edge.
Finally, when in the “normal” mode (white PAPER and black INK), there is always some annoying “rainbow” colors following the letters on the screen.
The TV itself is of the Electronic Tuning System type, the kind with push button tuning. There is a fine tuning control for each channel and automatic fine tuning once the control box door is closed. Am I correct in assuming these are not operating in the video mode? The rest of the controls are those you would normally find on any TV receiver.
I hope you have enough information to visualize my problem.
Jean-Claude Touzin
P. Q. Canada
Dear Mr. Touzin,
Your problems with the 2068 monitor display are quite common. Unfortunately, there’s no one thing that can be done to give youa crystal-clear display, short of buying a RGB interface and RGB monitor.
First the matter of the distortions with a black border. This ia a common problem with many monitors, especially those designed primarily for TV use with a monitor option “tacked on”. It occurs because the BLACK level (no light) voltage of the videosignal is quite close to the sync-pulse level; some monitors get “confused” by this. Sometimes this can be eliminated or reduced by the careful adjustment of the contrast and the horizontal hold controls. If not, your best bet would be to stick with colored backgrounds (e.g. blue). It has been reported that this can be eliminated on some monitors by direct-coupling the video output. On the 2068, thiscan be done by shorting C58 (inside the modulator case). I should mention, though, that in the event of a monitor malfunction, this could damage the video driver transistor Q2, and conceivably other parts of the computer.
The second problem, shadowing on the edges of certain colors, appears to be a characteristic of the 2068 and other computers that use the LM1889N modulator chip. Again, it seems to be worse with monitors that double as TVs, so short-cuts in monitor design could have something to do with this also. Sometimes the “sharpness” control can be used to make this less obvious. You might also be able to reduce this effect y adjusting the chroma crystal trimmer C18, located inside the little modulator box at the upper left corner of the 2068 board. Use a non-metallic screwdriver (available at electronics parts distributors) to slowly turn the little slotted adjustment. Note its original position so you can return to it if no improvement occurs. This might also help bring in your blues on a yellow background.
The “rainbow” colors with white characters on black is another problem relating to the monitor. You might have noticed the same effect on television, such as on pin-stripe suits (which is why such costuming is usually avoided in made-for-TV productions). The more expensive monitors have a “comb filter” which helps to reduce this. A competent TV repair person might be able to reduce this effect. Your best bet, though, with white/black screens is to simply turn the color control all the way to shut off the colors entirely. Or, again, go to a RGB system,in which each color is sent to the monitor on a seperate wire.
Lastly, “automatic fine tuning”, or in fact any sort of tuning, has nothing to do with monitor operation. The whole ideaa of a video monitor is to completely bypass the entire tuner section. It’s like your stereo; when you’re playing a record, the radio’s tuning dial has no effect. Just as the phonograph is connected directly to the audio amplifier, so also is the “monitor” video signal connected directly to the video amplifier.
To sum it all up, I’m afraid there’s not too much you can do. These and other display deficiences are on reason I prefer to use the ZX81/TS1000 with the Oliger video upgrade and a monochrome monitor. Its seems that what looks fine to some people is completely objjectionale to others. Don’t be afraid to use the controls provided on your set to get the best picture you can with whatever program you’re running at the time. Adjust your system as best as you can, and “grin and bear it”.-fn
Dear Editor,
What is confusing (to me) is probably very simple for you. When you write ZX 81 do you invariably refer to the TS1500? Specifically, does the Oligher TI Video Upgrade refer to the TS1500?
Sincerely,
James Smith
Bath, Maine
Dear Sir:
Your question about TS1500/ZX81 compatibility is an excellent one. In general, any program that was written for the ZX81 (aka TS1000) will run without change on the TS1500. There is only the rare exception; one of the most well known is the “Z-XLR8” Fast-load tape package. Until recently, it was thought that Z-XLR8 would not run on the TS1500. I have since discovered that this is only because of a minor hardware difference. By using a “reversed” load cable (i.e. connected “backwards”) Z-XLR8 works fine on the TS1500 (see figure 1).
However there are capabilities built into the TS1500 that are absent on the ZX81. Specifically, the TS1500 is capable of high-resolution displays far surpassing similar packages for the ZX81/TS1000. Greg Harder’s article in SyncWare News #3:4 describes this. His “Hi-Res Extended Basic” (available from Silicon Mtn. Computers, C-12 Mtn. Station Group box, Nelson, BC V1L 5P1, Canada) carries this technique into an actual programmer’s utility. It should be noted that these programs WILL NOT run on the ZX81/TS1000, whereas hi-res routines written for the ZX81/TS1000 will run on the TS1500.
The only other consideration is memory. Most ZX81/TS1000 owners have long since upgraded to 64K, so the occasional program (such as Memotext V3) presumes a 64K machine. 64K packs, as well as most other hardware add-ons, for the ZX81/TS1000 will work with the TS1500, but some of them are too long and interfere with the connectors on the back of the TS1500. On the ’81/1000, as you may know, has the connectors mounted on the side. So before you buy hardware addons for the TS1500, you should be sure that the mechanical dimensions are compatible with the 1500.-fn
FIGURE 1: Z-XLR8/TS1500 ADAPTER
Cut a standard cable in the middle, then splice it together “backwards”, i.e., the shield of one end goes to the center conductor of the other, and vice versa. Another way is to make up a backwards cable from scratch.
ONE WARNING:
Be sure to disconnect the MIC cable when using the backwards cable! This is ALWAYS a good practice, but it’s an absolute necessity when using an inverted load cable. Otherwise you will short the EAR output; at best, it won’t work, and at worst it might damage your recorder.
Dear Editor,
I have a problem that your readers may be able to solve.
Does anyone have a modification to the AERCO interface software for the TS 2068 to operate the new AK Royal Lettermaster daisy wheel printer?
I recently purchased this printer. It is very reasonably priced and should have wide distribution by now. AERCO has not responded to my request for help.
I am using an Olivetti inkjet printer with this combination (AERCO and TS2068) with full performance. I’m a long time subscriber and appreciate every word of your publication.
Charles Grosh
Pacific Palisades, CA
Dear Charles,
Thank you for your letter. I hope Syncware News and you continue together for a long time. I was unable to find an answer to your printer problem but I’ll put the question to our readership. Does anyone have an answer to the AERCO/Royal printer problem. If you do, let us know and we’ll pass the word along.-jm
Knighted SAVEs
Dear Editor,
I had been having trouble for some time while trying to save programs on my TS 2068 computer. I had tried implementing several possible solutions without any sucess. In a catalog I received from Knighted Computers of Fulton, NY was a suggestion that finally solved my problem. I’d like to share it with your readers.
The video generator in the 2068 is located near the left side of the computer. If your cassette recorder is also positioned on the left side of the computer, when doing a save, you may get interference that may cause an error when trying to load a tape. Knighted went on to suggest that the cassette be always placed on the right side of the computer, and as far away from the TV/monitor and computer as your cables will allow. This applies not only to cassette recorders, but to any data storage device you may be using.
I never had any trouble loading. Following their advice cured my saving problems that had existed for over a year.
Sincerely,
E. Swallow
Manchester, CT
More On Spikes
The purpose of this letter is to comment on and expand upon the article on page 3 of SWN 3:4 concering voltage spikes.
I have Relax Technology’s power control 3 unit under my monitor on the TS-2068 and everything (CPU, monitor, disk drives) is consequently “protected” from most eletrical problems. Since the spike protector is only one power cord it also makes it easy to unplug everything if a severe electrical storm is in the area. As I said before, “everything” is protected EXCEPT my telephone line coming into the modem. I knew I was going naked on the modem but really didn’t give proper consideration to the phone line until a really great electrical storm passed over the neighborhood at 3 AM on Saturday night. First thing Sunday, I turned on all the computers in the house to be sure they were working and breathed a sigh of relief. I tried for two days to reach a local bulletin board where I knew I had a message waiting and got only busy or no answer messages beforeit dawned on me that something was wrong. Ssure enough the static coming in the phone lines had rendered the modem deaf and dumd. I am thankful that the MOV just inside the line connection stopped it there and it didn’t go into the edge connector and on to the CPU or some other disaster area. I now have a Tripp-Lite modem spike arrestor, a new TS-2050 modem on order, and, thankfully a promise of a check from my homeowners insurance carrier for the replacement modem, plus a new respect for the importance of surge protection on ALL of my computer equipment.
Your readers might like to know of the importance of telephone line suppressors as a addenda to your former article. Reading about it is an eaiser way to learn than I had.
Sincerely,
Phillip Stevens
Des Moines, Iowa
Print Message Notes
The article on using the message routine in the 2068 that appeared in the March-April issue was useful. However, two problems exist with the routine.
First, if a print statement is before the message routine call (same line) the 2068 prints your message on the upper screen (the exact location depends on the last print location used). This can be correted by calling the 2068 routine referred to as SELECT with A=0, setting the channel to the lower screen.
The second problem is the position of the flashing cursor at the end of the message. This, along with the echo of any keys pressed immediately after the message, tends to be unprofessional in appearence. To eliminate this, reset bit 3 of FLGS (prepares the computer to receive a keyword) and set bit 5 of TVFLGS (makes cursor non-visible and clears the lower screen when key pressed and echos it).
The following code is the corrected version. Note that register A must contain the message number when this routine is called.
ERROR PUSH AF F5 : save message no.
LD A,00 3E00 : set channel for
CALL 1230 CD3012 : bottom of screen
POP AF F1 : recover message no.
LD DE, MSSG 11 MSSG : MSSG=start of messages
CALL msgs CD3F07 : output message
LD HL, flgs 213B5C : reset bit 3 of flags
RES 3, (HL) CB9E : (for keyword)
INC HL 23 : set bit 5 of tvflags
SET 5, (HL) CBEE : (for clear bottom)
JP 0E2F C32F0E : jump to control loop
MSSG Code of message(s) starts hereSincerely,
James Hunkins
Rapid City, SD
Canada Customs
If you’re supplying computer goodies to customers or pals in Canada, the following tips will help the fellow on the receiving end cope with the Customs service.
1: Go to the trouble of filling out a Customs Declaration. It will take you less than a minute, and could save your customer lots of time and hassles.
2: If you’re sending hobbyist software or hardware (as most if not all of the stuff for our machines should be considered), MARK IT AS SUCH. When customs people see the word “Computer,” they immediately think IBM stuff worth hundreds of dollars. Indicate that the stuff you’re sending is for experimenter use; the watchword is HOBBY.
3: When sending hardware or parts, mark it as COMPUTER hardware or parts. Though it doesn’t make any sense, the duty rate for ELECTRONIC parts is over 3 times as high as the rate for COMPUTER parts, even though most components could logically be classified either way.
4: Mark packages with programs on EPROM as COMPUTER SOFTWARE (which it is), not as computer hardware or parts. This is because hardware is dutiable, software is not.