Anyone with a sighthound or lurcher would recognise that, rocket or asleep, four legs antenna for dog radio, but they are wonderful when they run,not so good if they spot rabbit, might have to Jazz dark glasses
Having entered my sixties without any serious work injuries over the years, coming off ladders thee times but always onto a soft landing, drilling through a finger or two, I thought that now I live the quiet life, a bit of inspection a small amount of installation,that I would remain injury...
I saw some figures I think on the IET site around ten years ago, that gave PVC a lifespan of 69 years subject to full load for a quarter of the time, very few domestic circuits would work that hard. I'll attempt to find the source of the figures this week.
In the end we simply test it and...
A long term customer had an extensive model railway, which was always in the middle of being modified whenever I was there. After years of visits I turned up one day to find it intact and asked to see it running. The auto points turned out to be his wife flying around through room operating them...
Worst I've found , mostly because I'm sure the customer did it himself An alarm panel supplied via an old Wylex switch fuse unit with four core alarm cable, the incomer fed from the meter terminals. 30 amp bs3036 in SF but tiny cable connected red live, black neutral, yellow CPR, who can accuse...
Hi , my oddest job was a rewire in a house the customer was going to vacate for a week in return for a 500 quid price reduction. On the second day a builder turned up, saying he was to knock through from through lounge to dinning room and into the garage from the hall to allow a downstairs...
I like playing with logic gates, the wonders of truth tables. later processor alarms offeredbetter function than fixed logic gates. Agree about Omnicom. First reset on scantronic putting nvm eight legged chip back in with power on a worry. Off to bed in a min, rescue dog asleep, sofa not going...
They called seemed to be in Liverpool,ADE ctec McDonalds.I might still have an early ADE green button isolate zone two, then logic 4, optimal , great panels
I had not noticed until a few minutes before your reply the alarm connection, had bash in the eighties making our own pcbs, not really worth it, early days of ADE , their panels were cheaper, still have loft full of old panels. loved early optimal some still around, cationic for better jobs.This...
Hi Tazz, I'm not looking to dodge the question, I don't have my semiconductor book to hand , although I think that is pretty bog standard diode, I don't know offhand what it's parameters are. However I will say that my experience of needing to suppress back emf was for alarm systems from years...
Hi , we must stop meeting like this. I'm not saying that varistors have no use. Just that when reducing back emf that diodes will hold it lower, I don't dispute that varistors will do things that diodes will not, Cheers
Hi thanks for the reply. I thought I had accepted in my last post that varistors had a role as General purpose suppressor. However because they are not polarity sensitive and also need to allow the circuits normal voltage they will not hold the reverse voltage down to 0.6V or.1V that diodes...
A voltage dependent resistor would not be polarity sensitive, 0 12 the same as 12 0. Years ago 555 timer chips were triggered by a negative pulse to pin 2. This pulse could be tiny, so small that even a silicon diode at around 0.6V when forward biased by the back elf would not stop the timer...
Hi , I'm far to old to be crawling under the floor or squirming passed roof trusses in lofts, my eyesight is such that I spent ten minutes trying to hook a neutral before being told it was a shadow, screws no longer seem to have identifiable heads. I notice RS on this site and they are a source...
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