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Anyone Heard of a Palomar VC-300 voice scrambler

  • Thread starter Thread starter Rustynail
  • Start date Start date
First post was from 1969!
Hmm, from before the internet? Not really.

That date is a quirk of the way Unix-type operating systems store date and time. It's a stupidly-long binary number. It counts up 60 times a second from a starting date/time of one second after midnight January 1, 1970. Just one problem. This forum was transferred from a non-Unix to a Unix-flavor operating system ten or twelve (?) years ago. Moving posts from the old system to the new one would have required translating the date attached to every post from the old date/time system to the new one.

Didn't happen. As such, the new system interpreted the scrambled date/time data as one second before midnight Dec 31, 1969, just before the Unix-standard 'zero' reference for its binary date data format.

Yeah.

But any time you see a date on the internet of Dec 31, 1969 it reveals a glitch in translating data from a (say) Micro$oft-based system to a Unix-type environment.

Quirky 541t.

73
 
Must be a lot of youngsters in here if they didn't know the internet didn't exist publicly back then.
 
Hmm, from before the internet? Not really.

That date is a quirk of the way Unix-type operating systems store date and time. It's a stupidly-long binary number. It counts up 60 times a second from a starting date/time of one second after midnight January 1, 1970. Just one problem. This forum was transferred from a non-Unix to a Unix-flavor operating system ten or twelve (?) years ago. Moving posts from the old system to the new one would have required translating the date attached to every post from the old date/time system to the new one.

Didn't happen. As such, the new system interpreted the scrambled date/time data as one second before midnight Dec 31, 1969, just before the Unix-standard 'zero' reference for its binary date data format.

Yeah.

But any time you see a date on the internet of Dec 31, 1969 it reveals a glitch in translating data from a (say) Micro$oft-based system to a Unix-type environment.

Quirky 541t.

73
There are remnants of the old EZboard forum still there. Back when we had limited bandwidth and suffered from denial of service attacks, from idiots flooding the forum....
Ya the good old days when you had to go look up tech books in the card file.

73
Jeff
 
I know this is a very old thread, but i picked one up dirt cheap , it has very low echo modulation and only repeats like 2 times. like hello hello then done no real depth like it should have and this is with time and echo volume at max. finding any info on these vc-300 and vc-200 versions is like finding a needle in the ocean or where the mob hid Jimmy Hoffa's body ,,,, there is online manual and schematic for the more popular vc-100 but they are completely different so that doesnt help, what i have tried: I pushed on all connections from board under faceplate going to main board to see if something is loose NOPE, pressed on the board around the echo section ( Mitsubishi ) mn3008 ,mn3101, NEC c75c2? ( cant see last number due to some dot over it ) and toshiba ta753324 chips looking for a possible bad solder joint nope, looked to see if bulging or blown caps due to its age Nope, cleaned all pots with deoxit nope,
everything else works fine the mic gain, the rec, monitor/talk back, mix, code and pee ( beep/doorbell) just no real echo, like i said it kind of works as you can hear it a bit with the talkback cranked full volume or using a monitor radio
it gets bit louder using my galaxy deck mic with the echo fully off but than of course its using a amplified input from the mic , also using a stock mic it's there just real quiet unless i talk REALLY LOUD into it and like i said only repeats like 2 times and no depth a manual or schematic would be wonderful any ideas on where to look? i'm thinking its obvious a voltage problem somewhere like1 of the 7 of transistors in that area are not getting power one has to be some type of audio amplifier to the echo volume none look popped, everything intact no cracks etc i see no darkened or blown resistors in that area either or someone still have one floating around with a manual or schematic ? or some idea where to look?
 
bulging or blown caps due to its age
That kind of electrolytic cap seldom looks bad. The VC box is an entirely low-energy device that consumes just a little power supply current. There's not enough extra energy available to make a capacitor swell or pee on the floor. Takes more power than the VC can supply. It can't be any less than 45 years old. Age alone causes them to fail. A quick poke across each electrolytic cap with a ESR meter would no doubt reveal parts of your problem. At least you can do that with the capacitor in the circuit. The faults you mention are consistent with electrolytic caps that are old enough to also act like resistors, changing the circuit. And not for the better. The labor to poke about and test parts would be better spent making a list of them and replacing them all.

Or just replace any that test bad. Over and over until they all get changed. We call that "electronic whack-a-mole". Kinda like a row of dominoes. Once the first couple of them fall, the rest will follow.

The only way anyone will ever see a schematic will be to reverse-engineer it. Trace every circuit and component to draw up a schematic. Not on my bucket list.

73


73
 
thank you Nomad, i will get a esr meter and do that wasn't sure anyone would reply to such a old thread , btw are you the one selling the 4 pin conversion for the 2000 and tram 300 on ebay? if so it works like a charm on my 2K, so much nicer not having that big old 4 to 5 pin adapter
 
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Thank you Nomadradio Faulty caps it's working now, replaced 6 caps that were showing bad with my esr meter c119 i'm sure was the main culprit its right next to the 3008 chip was showing 470uf when it should have been .047uf after i pulled that out put in the correct value POOF ECHO ECHO ECHO :-)
 

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