MiniMicroMart was a computer hobbyist store based out of Syracuse, New York that catered to MIL Mod 8/80, S-100 and other early computer enthusiasts in the mid to late 1970s.
I have recently got a few more MiniMicroMart Brochures which I have added to the MiniMicroMart PDF file under the Mod 80 documentation section. This adds about 42 pages to that file.
MiniMicroMart was a computer hobbyist store based out of Syracuse, New York that catered to MIL Mod 8/80, S-100 and other early computer enthusiasts in the mid to late 1970s.
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Today, I received a pair of giant binoculars I ordered from a local astronomy supplier. I had a pair of Burgess 20x80 binoculars, but they went out of collimation. I recollimated them myself, but they would not get even close, so in the end I decided to send them to my junk box in case I decide to make something else of them. The company no longer exists, so they cannot repair them.
These new ones are by Celestron and are much heavier and are better made. I will have to make a better mount for them, as my existing bino mount is a bit too small for a 4 kg load. So far I love these new binoculars. They are sharp and crisp, and the collimation is bang on. I recently obtained this beautiful set of serienscheine from the city of Oldenburg. This set shows the development of Oldenburg in the year 2000 as the artist Georg-Emil Baumann imagined it in 1922. This particular set of notgeld (emergency money) was approved by the city of Oldenburg for Oldenburg Week.
Oldenburg Week was a patriotic event with a broad participation of Oldenburg residents. According to the city's mayor, "The diverse events of the Oldenburg Week are intended to testify to the heights of Germanic culture. Church ceremonies in Plattdeutsch will begin the week and there will be masterpieces of drama and music, lectures by German thinkers, presentations of great technical plans and competitions full of physical grace." The front of all banknotes was the same, except for the denomination. These notgeld pieces were available in the following denominations: two notes each: 1M, 2M and 3M. The money was produced by the Ad. Essich Printing Works. In December last year I ordered these MTX-90 glow discharge thyratrons from Bulgaria. They took a bit of time to arrive, but they were well priced and they should be handy for some neat projects. They can be used converting low-power electrical signals, as well as for operating as relays. Because they contain neon at low pressure, they also glow when they conduct, so they can serve as indicators as well.
Back in December 2021, I tried to make this old school transistor radio from a book called The Boys' 2nd Book of Radio and Electronics by Alfred P. Morgan (1957). Unfortunately it was not successful. I thought the problem was because the loopstick I used was not quite correct. Recently I was able to finally buy the Miller 6300 loopstick that was supposed to be used in this circuit. However that did not really fix the problem. After posting to a FB group, someone spotted a wiring error, and also suggested adding a 10kohm resistor. Indeed it did turn out I had a wiring issue which was the cause of my troubles. Not sure how I missed that twice before, but I did.
The addition of the 10 K resistor was not absolutely necessary, but it did result in better audio, so I kept it in. It is a strange radio. To tune it, you use the loopstick, and fine tune it (or tune out interfering stations) with the variable capacitor. It works, but you do need a long wire antenna and ground. It is basically a crystal radio with an amplifier. It is hard to eliminate a local station, but it does eventually reduce it enough so other stations are easily heard. Here is a nice 50 pfg notgeld note from the town of Bad Salzuflen. The cat, a symbol of cleanliness, was the part of the logo of the Hoffmann's Starch Factory. On this notgeld it is shown keeping its coat nice and shiny clean. I believe the script is written in old German or local language as it did not fully translate in Google for me. I believe it translates to "As long as the white cat keeps its coat clean, So will Salzuflen's strength shine in all the world."
Today I got a spool of 25 feet of "antenna wire" which came on a convenient winder. It is surprisingly small. I thought this would be 4 or 5 inches wide, but it is actually more like 2 inches wide and about 1.5 tall. I might pack this with my Paraset.
The Rogers 120 had several old paper capacitors in it. Most appeared to be working, but since these were nearly a 100 years old, I decided to replace the internals with modern equivalents. As you can see from the photos below, the new components can be easily hidden inside the original cases, giving the appearance that they were unchanged. Because I wasn't quite sure of the capacitance (sometimes it changed in successive readings), I opted to up the value, when in doubt. 0.6 MFD sometime read 0.75 MFD, so I upped the value to 1 MFD. Similarly, one of the 1 MFD capacitors read 1.5 MFD at one point, so I opted to go with 1.5 MFD. None of these were actually labeled, nor did the schematic match what was actually found. A few months back my Google drive got filled, so I had to delete a number of files to clear up some space. Unfortunately that meant removing files that were linked to from this site.
I have since uploaded all the files to DropBox (which has more free space) and revised the link. All the MIL Mod 8 and Mod 80 links and other misc. links should work now. If not, please send me an email, and I will repair the remaining ones. Today I picked up an early Model 120 Rogers Batteryless Radio from a person in London, Ontario. A Type 120, which is one of the first series of AC operated radios produced in Canada (if not the world). It was first demonstrated in August 1925 at the Canadian National Exhibition (CNE) in Toronto.
The unit was in exceptional condition. Whoever owned it over the years kept must have kept it as a display piece at least as there was no moisture damage or rust to speak of. The cloth covered wire looks like it was made yesterday. There is no mold or fading of the colours. The set even came with the instruction card still attached to the inside cover. The only issues I could see was a disconnected wire (to the speaker jack) and a frayed power cable (as is normal for such old equipment). All tubes were present (Rogers #32). In the power supply one of the two Rogers RX-100 tubes (half wave rectifiers) was missing. |
AuthorCharles Baetsen holds a Bachelor and a Master's degree in Engineering Physics from McMaster University in Hamilton, Canada. Archives
February 2024
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