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"Joe McElvenney" wrote in message ... Hi, Mouser have some NEC pre-scalers (3GHz max) for $2.92 a throw. Any idea of the NEC part number ? Thanks |
Hi,
They are listed at - http://www.mouser.com/catalog/615/217.pdf and NEC have a data sheet on-line if you do a quick Google. I should point out that they are really only simple dividers with none of the front-end bits necessary to make a complete prescaler. I was thinking of using one with an old Racal 1991 VHF counter that has the built-in maths capability required to enable a non-decade pre-division. Cheers - Joe |
Hi,
They are listed at - http://www.mouser.com/catalog/615/217.pdf and NEC have a data sheet on-line if you do a quick Google. I should point out that they are really only simple dividers with none of the front-end bits necessary to make a complete prescaler. I was thinking of using one with an old Racal 1991 VHF counter that has the built-in maths capability required to enable a non-decade pre-division. Cheers - Joe |
I have thought about using one of the modern SM PLL chips such as the
National LMX2326 which can be progammed to give any division over a wide range (you do need a controller though to drive it) - you can access the main divider output directly and ignore the phase divider. These are widely available and pretty cheap. I would think you could do one one these "dead bug" with care, though they are SSOP. Of course if you are doing a PLL, why not use the whole chip? Richard Harry (SM0VPO) wrote in message ... Hi all, I am having a spot of bother with prescaler chips. Basically I need to find one at the right price and availability. US$5 each is reasonable, but where from? Is there one available that is not obsolete? I live in Sweden and my local component shop is ELFA (Swedens answer to RS). They don't sell ANY digital divider that operates above 50MHz, except for the 74F163 and I cannot come up with a reliable interface circuit to couple an oscillator into it at over 100MHz. I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a reliable source. I bought a couple, but that source dried up. All I need is a divider chip that will accept a small signal up to 150MHz, is available, cheap(ish) and will divide down to under 10MHz so that I can use CMOS to process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz prescaler would do. I have used "Teleport" to download over 50,000 pdf datasheets without any luck. I have gone through most of them, but it takes a fair bit of time. If anyone has a helpful suggestion I would appreciate it. BR from Harry - SM0VPO http://w1.859.telia.com/~u85920178/ harryvpo (at) hotmail (dot) com |
I have thought about using one of the modern SM PLL chips such as the
National LMX2326 which can be progammed to give any division over a wide range (you do need a controller though to drive it) - you can access the main divider output directly and ignore the phase divider. These are widely available and pretty cheap. I would think you could do one one these "dead bug" with care, though they are SSOP. Of course if you are doing a PLL, why not use the whole chip? Richard Harry (SM0VPO) wrote in message ... Hi all, I am having a spot of bother with prescaler chips. Basically I need to find one at the right price and availability. US$5 each is reasonable, but where from? Is there one available that is not obsolete? I live in Sweden and my local component shop is ELFA (Swedens answer to RS). They don't sell ANY digital divider that operates above 50MHz, except for the 74F163 and I cannot come up with a reliable interface circuit to couple an oscillator into it at over 100MHz. I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a reliable source. I bought a couple, but that source dried up. All I need is a divider chip that will accept a small signal up to 150MHz, is available, cheap(ish) and will divide down to under 10MHz so that I can use CMOS to process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz prescaler would do. I have used "Teleport" to download over 50,000 pdf datasheets without any luck. I have gone through most of them, but it takes a fair bit of time. If anyone has a helpful suggestion I would appreciate it. BR from Harry - SM0VPO http://w1.859.telia.com/~u85920178/ harryvpo (at) hotmail (dot) com |
Frank Gilliland wrote Man, if THIS ain't a trip -- a well-known, over-rated internet homebrew tech asking for help for a simple prescaler. And why not? I am the first to admit lack of experience any a field. You should not be afraid to ask, either. You learn a lot more than you do when you simply site there and ridicule people. ... over-rated ... ??? See what I mean ??? Superfluous words conveying no meaning, other than displaying emotions that one would hide in public to avoid embarrasment. Hey Harry, don't you know that the basic freshman-lab-grade Class B or C amplifier is nothing more than a divide-by-2 counter? If you have a bunch of 2N2222's, 2N2907's, or any transistor with an Ft above your high-freq limit, you have a divide-by-(n x 2) counter. Any advanced homebrewer should know that stuff cause it's basic theory. Not available in Sweden, just the usual 300MHz unity-gain (BC547, 557, etc), and the circuit stops operating at about 100MHz when the gain/pcb has become useless. I need RF transistors that are not available. ELFA only have no RF small signal devices. And for you to post such a question in alt.radio.pirate.... that's pretty pathetic, Harry. I was a pirate myself, LONG before I became an amateur. I have a lot of respect for the knowledge and experience of some of these so-called "pirates". I wonder how just many "pirates" you have spoken to on the HF bands? Certainly more than 0 and you were not even aware of it. Very best regards from Harry ( Writing from home this time ) harryvpo (at) hotmail (dot) com |
Frank Gilliland wrote Man, if THIS ain't a trip -- a well-known, over-rated internet homebrew tech asking for help for a simple prescaler. And why not? I am the first to admit lack of experience any a field. You should not be afraid to ask, either. You learn a lot more than you do when you simply site there and ridicule people. ... over-rated ... ??? See what I mean ??? Superfluous words conveying no meaning, other than displaying emotions that one would hide in public to avoid embarrasment. Hey Harry, don't you know that the basic freshman-lab-grade Class B or C amplifier is nothing more than a divide-by-2 counter? If you have a bunch of 2N2222's, 2N2907's, or any transistor with an Ft above your high-freq limit, you have a divide-by-(n x 2) counter. Any advanced homebrewer should know that stuff cause it's basic theory. Not available in Sweden, just the usual 300MHz unity-gain (BC547, 557, etc), and the circuit stops operating at about 100MHz when the gain/pcb has become useless. I need RF transistors that are not available. ELFA only have no RF small signal devices. And for you to post such a question in alt.radio.pirate.... that's pretty pathetic, Harry. I was a pirate myself, LONG before I became an amateur. I have a lot of respect for the knowledge and experience of some of these so-called "pirates". I wonder how just many "pirates" you have spoken to on the HF bands? Certainly more than 0 and you were not even aware of it. Very best regards from Harry ( Writing from home this time ) harryvpo (at) hotmail (dot) com |
what frequency steps are you looking for harry????
if its for the broadcast band then the philips range of tsa5511/12/14 are cheap and have upper operating range of 1300mhz, only trouble with them is 50khz steps..pic codes available on the net...otherwise the mc 145170 is a good choice, operates up to 170mhz..but is serial controlled as well.... g0zen simon "Richard Hosking" wrote in message . au... I have thought about using one of the modern SM PLL chips such as the National LMX2326 which can be progammed to give any division over a wide range (you do need a controller though to drive it) - you can access the main divider output directly and ignore the phase divider. These are widely available and pretty cheap. I would think you could do one one these "dead bug" with care, though they are SSOP. Of course if you are doing a PLL, why not use the whole chip? Richard Harry (SM0VPO) wrote in message ... Hi all, I am having a spot of bother with prescaler chips. Basically I need to find one at the right price and availability. US$5 each is reasonable, but where from? Is there one available that is not obsolete? I live in Sweden and my local component shop is ELFA (Swedens answer to RS). They don't sell ANY digital divider that operates above 50MHz, except for the 74F163 and I cannot come up with a reliable interface circuit to couple an oscillator into it at over 100MHz. I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a reliable source. I bought a couple, but that source dried up. All I need is a divider chip that will accept a small signal up to 150MHz, is available, cheap(ish) and will divide down to under 10MHz so that I can use CMOS to process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz prescaler would do. I have used "Teleport" to download over 50,000 pdf datasheets without any luck. I have gone through most of them, but it takes a fair bit of time. If anyone has a helpful suggestion I would appreciate it. BR from Harry - SM0VPO http://w1.859.telia.com/~u85920178/ harryvpo (at) hotmail (dot) com |
what frequency steps are you looking for harry????
if its for the broadcast band then the philips range of tsa5511/12/14 are cheap and have upper operating range of 1300mhz, only trouble with them is 50khz steps..pic codes available on the net...otherwise the mc 145170 is a good choice, operates up to 170mhz..but is serial controlled as well.... g0zen simon "Richard Hosking" wrote in message . au... I have thought about using one of the modern SM PLL chips such as the National LMX2326 which can be progammed to give any division over a wide range (you do need a controller though to drive it) - you can access the main divider output directly and ignore the phase divider. These are widely available and pretty cheap. I would think you could do one one these "dead bug" with care, though they are SSOP. Of course if you are doing a PLL, why not use the whole chip? Richard Harry (SM0VPO) wrote in message ... Hi all, I am having a spot of bother with prescaler chips. Basically I need to find one at the right price and availability. US$5 each is reasonable, but where from? Is there one available that is not obsolete? I live in Sweden and my local component shop is ELFA (Swedens answer to RS). They don't sell ANY digital divider that operates above 50MHz, except for the 74F163 and I cannot come up with a reliable interface circuit to couple an oscillator into it at over 100MHz. I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a reliable source. I bought a couple, but that source dried up. All I need is a divider chip that will accept a small signal up to 150MHz, is available, cheap(ish) and will divide down to under 10MHz so that I can use CMOS to process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz prescaler would do. I have used "Teleport" to download over 50,000 pdf datasheets without any luck. I have gone through most of them, but it takes a fair bit of time. If anyone has a helpful suggestion I would appreciate it. BR from Harry - SM0VPO http://w1.859.telia.com/~u85920178/ harryvpo (at) hotmail (dot) com |
"Joe McElvenney" wrote in message ... Hi, Mouser have some NEC pre-scalers (3GHz max) for $2.92 a throw. Cheers - Joe Hi Joe, Many thanks for the information. You have been a great help; exactly what I was alooking for. I keep having trouble buying this sort of specialised RF component. Mant thanks again for your help. BR Harry |
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