Loved the Thandar line back in the days. Inexpensive but generally good gear for the hobbyists and even found a few in our university labs. Nice to see good old traditional components and PCBs that you can work on and fix!
Thomas you are so right about Sir Clive Sinclair, really a genius way before his time.. Had a Calculator once, and my biggest wish for my 15 years birthday, was a solder-yourselves-ZX80 ;-) Really nice fixup - Good work
my first computer was a ZX spectrum 48k with opus discovery 3.5" disk drive, single sided 180k but wow it loaded the full memory in a few secs, amazing power boost, versus cassette that took many minutes, and often failed loading. I think you are a few years older than me, that is why you talk about the ZX80 :-)
I did buy one of those a few years ago and it was in almost new condition except the battery holder was cracked as is common for these holders. There were 11 years overdue batteries... that is over the date printed on the batteries... luckily they had not leaked at all. I took out the battery holder and mounted a small analog power supply and removed the DC plug. It s a nice well functioning counter wich I have used a lot already. Thanks for the upload.
Sinclair also fitted the reversed power socket on the zx spectrum, there was no reason for it. You have a nice little counter there. Maybe a tiny ovan for the crystal to keep it stable.
Hi Thomas, nice little counter and a cool transistor stop. The power socket connection is quite common for devices with built-in batteries, and unfortunately it is also common that it does not have reverse polarity protection. It's been about half a year since I repaired a small mixing desk for a colleague from work, bought it on an ad without an original power supply, grabbed the first power supply I found at home with the appropriate voltage and turned it on without checking the polarity. When I told him that he was stupid, I got the answer "There is always a + on the center contact", so I misled him. I was looking in the supply of power connectors and it could be a 6.3 / 3.1 size, at first glance it looks a lot like a 5.5 / 2.5. If you stop for coffee, I can give you one with an adapter 😂 In the old workshop, I had a meter with a damaged reflective layer on the LCD, so I removed the reflective layer and created a transmission display using an LED backlight - it looked luxurious. Nice day 🙂 Tom
i imagine people will loose or swap power supply units for small electronic equipment with one that just plug it, without double check voltage or polarity ?? an easy way to brake stuff, that is why all units should have huge voltage survive range and polarity protection, that is just not the case always :-)
I found out the hard way about the centre negative DC socket on Thandar kit when I plugged in a centre positive PSU, I had the 600MHz LED version of this and managed to kill the ICM7216 chip, fortunately Aliexpress came to my rescue and I've since upgraded to a Racal 1998 but i did love my Thandar while I had it.
I am from Denmark, postage is terrible expensive, the ZX81 do pop up now and then here, I am more hot for a ZX-spectrum since it was my first computer, and i might still be able to figure out how to use it :-) one day.. maybe :-)
Loved the Thandar line back in the days. Inexpensive but generally good gear for the hobbyists and even found a few in our university labs. Nice to see good old traditional components and PCBs that you can work on and fix!
Interesting transistor bodge repair! Nice freq counter, zebra strips, arg.... ~Jack, VEG
Thomas you are so right about Sir Clive Sinclair, really a genius way before his time.. Had a Calculator once, and my biggest wish for my 15 years birthday, was a solder-yourselves-ZX80 ;-)
Really nice fixup - Good work
my first computer was a ZX spectrum 48k with opus discovery 3.5" disk drive, single sided 180k but wow it loaded the full memory in a few secs, amazing power boost, versus cassette that took many minutes, and often failed loading. I think you are a few years older than me, that is why you talk about the ZX80 :-)
😉👍 you are so right Thomas..
I did buy one of those a few years ago and it was in almost new condition except the battery holder was cracked as is common for these holders. There were 11 years overdue batteries... that is over the date printed on the batteries... luckily they had not leaked at all.
I took out the battery holder and mounted a small analog power supply and removed the DC plug.
It s a nice well functioning counter wich I have used a lot already.
Thanks for the upload.
wow thanks, nice to hear they still exist out there
Sinclair also fitted the reversed power socket on the zx spectrum, there was no reason for it.
You have a nice little counter there.
Maybe a tiny ovan for the crystal to keep it stable.
thanks for the info, i will try to remember this if I ever get a ZX spectrum again,
Hi Thomas, nice little counter and a cool transistor stop. The power socket connection is quite common for devices with built-in batteries, and unfortunately it is also common that it does not have reverse polarity protection. It's been about half a year since I repaired a small mixing desk for a colleague from work, bought it on an ad without an original power supply, grabbed the first power supply I found at home with the appropriate voltage and turned it on without checking the polarity. When I told him that he was stupid, I got the answer "There is always a + on the center contact", so I misled him. I was looking in the supply of power connectors and it could be a 6.3 / 3.1 size, at first glance it looks a lot like a 5.5 / 2.5. If you stop for coffee, I can give you one with an adapter 😂
In the old workshop, I had a meter with a damaged reflective layer on the LCD, so I removed the reflective layer and created a transmission display using an LED backlight - it looked luxurious.
Nice day 🙂 Tom
i imagine people will loose or swap power supply units for small electronic equipment with one that just plug it, without double check voltage or polarity ??
an easy way to brake stuff, that is why all units should have huge voltage survive range and polarity protection, that is just not the case always :-)
I found out the hard way about the centre negative DC socket on Thandar kit when I plugged in a centre positive PSU, I had the 600MHz LED version of this and managed to kill the ICM7216 chip, fortunately Aliexpress came to my rescue and I've since upgraded to a Racal 1998 but i did love my Thandar while I had it.
ahh.. so many nice stuff on your chanell.. 🙂 Where i can buy that blue pen-screwdriver like yours? thx
i think it is the adjustment pen / screwdriver type of thing you mean ? try to put this into google
bourns trimmer pen
amazon search words : Potentiometer Tools & Hardware ADJUST. TOOL
👍
Hi Thomas, do reside in the States, if so I would like to send you my ZX81 if you are interested.
I am from Denmark, postage is terrible expensive, the ZX81 do pop up now and then here, I am more hot for a ZX-spectrum since it was my first computer, and i might still be able to figure out how to use it :-) one day.. maybe :-)