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Crystals!, we don't need no stinkin crystals!.
Posted: Mon Mar 31, 2003 11:51 pm
by Cowthief
Hello.
Saw this cute little board, PLL synt' thing, you select offset, base, basecount (steps) and stepcount (channels).
Well, put one in a HT220, first offset to RX, 455KHz, second,0
O.K., we got 256 channels, really tight freq' ultra stable, and the things are cheap to make, nothing more than a PLL chip support parts.
Made for the down-under CB nit-wits, UHF, but the thing does work.
I would like to find the chip itself, remember, CB crap is branded X.
The things sell for around $45. american, so there is not much to it.
Just think, for the cost of ONE set of channel elements in a MT500, you could have 256 channels, and not RSS hoops, and remember, it works at the crystal osc level, so one board could do VHF LO/HI, UHF, whatever.
Lets get creative here, something to think about,, the batlabs exclusive,,,.
Thank You.
Posted: Tue Apr 01, 2003 8:42 am
by W4WTF
Where did you see this? Got any links?
No links.
Posted: Tue Apr 01, 2003 1:06 pm
by Cowthief
Hello.
No links, just walked into a CB shop, they are pushing the "replacement" for standard CB, what else, GMRS.
In with all the range extendo-echo reverb junk they sell, they had this little board.
The guy said it had been around the shop for a while, perhaps years.
CB shops also sell cheap, $25. frequency counters, that have an adjustable base count, you can, for example, connect one to the LO of a radio, adjust the BC, so the display is correct freq'.
I very seldom find something worthwhile in CB shops, but sometimes.
Thank You.
Posted: Tue Apr 01, 2003 1:22 pm
by wa2zdy
This is not a new idea. Check out this link:
http://www.geocities.com/mikeht220/220synthesizer.html
This article originally appeared in 1976.
HT220
Posted: Tue Apr 01, 2003 5:01 pm
by Cowthief
Hello.
Never said this was a new idea, or old idea, just a good idea.
The unit uses a single chip to do all the synthesizer.
Does anyone else think this is worthwhile?.
Thank You.
Re: HT220
Posted: Tue Apr 01, 2003 9:53 pm
by n8uhn
yeah,
i do.
maybe then i can put the rt and ra moto base
stations to good use - or a few of the other rockbound radios i have laying around.
Cowthief wrote:Hello.
Never said this was a new idea, or old idea, just a good idea.
The unit uses a single chip to do all the synthesizer.
Does anyone else think this is worthwhile?.
Thank You.
Posted: Sat Apr 05, 2003 9:33 am
by perthcom
that link looks like a unit that I built for a local ham back when I was in high school.. would have been about 1976!
It was a tad microphonic if i remember!
Crystals
Posted: Sat Apr 05, 2003 4:25 pm
by Cowthief
Hello.
The unit I am excited about is based on a phillips IC.
The entire unit, including a few support parts, will fit in the palm of your hand, closed, remember, this is ONE IC for everything.
Harmonics, a thing of the past, this thing is analog, all the way, in that it is a mixing PLL, not a division PLL, so everything is sine wave in the RF path.
Digital is limited to control, but then, this is done by vericaps, again analog.
Phillips rep is getting me a few samples, there are several chips to choose from, and every chip is under $5.00, in singles.
Posted: Sat Apr 05, 2003 4:33 pm
by wa2zdy
I hope you'll keep us up to date. I have a bunch of unused MT500s here that would be fun to tinker with. I have one more now that the 2m ham repeater I've been involved with has been taken off the air. I sure don't see much use for buying rocks for them. Pointless, great as the radios are.
It sounds interesting so far though, let us know!