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#1
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Although I have been interested an amateur radio for about 30 years, I've
never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. |
#2
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The NE602 is a favorite with the Ham crowd. Plenty of projects found on the
web, including FM. Cheers "Richard" wrote in message ... Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. |
#3
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The NE602 is a favorite with the Ham crowd. Plenty of projects found on the
web, including FM. Cheers "Richard" wrote in message ... Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. |
#4
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![]() "Martin Riddle" wrote in message nk.net... The NE602 is a favorite with the Ham crowd. Plenty of projects found on the web, including FM. Cheers Hi It could be that the ICs I'm searching under are not popular with homebrewers. Or, that articles are in printed publications, (like Practical Wireless etc) or folks just rely on application notes. ICs I've mentioned are ones typically found in your average AM/FM radio perhaps in the '90's. LA1177: Electronic Tuning-Use FM Front End for CarRadio, Home Stereos. LA1266: AM/FM Tuner Syatem of Electronic Tuning Type. LM7000: Direct PLL Frequency Synthesiser for Elexctronic Tuning. LA1235:FM IF Sysyem Applications. But, I think if anyone wants to mess with these ICs it's more economical to get some 90's radio, take it apart and rebuild it, with mods. That a way you get all the hard-to-get bits, like the display. So, these could be the reasons I've not found many articles incorporating the ICs I mentioned. "Richard" wrote in message ... Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. |
#5
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![]() "Martin Riddle" wrote in message nk.net... The NE602 is a favorite with the Ham crowd. Plenty of projects found on the web, including FM. Cheers Hi It could be that the ICs I'm searching under are not popular with homebrewers. Or, that articles are in printed publications, (like Practical Wireless etc) or folks just rely on application notes. ICs I've mentioned are ones typically found in your average AM/FM radio perhaps in the '90's. LA1177: Electronic Tuning-Use FM Front End for CarRadio, Home Stereos. LA1266: AM/FM Tuner Syatem of Electronic Tuning Type. LM7000: Direct PLL Frequency Synthesiser for Elexctronic Tuning. LA1235:FM IF Sysyem Applications. But, I think if anyone wants to mess with these ICs it's more economical to get some 90's radio, take it apart and rebuild it, with mods. That a way you get all the hard-to-get bits, like the display. So, these could be the reasons I've not found many articles incorporating the ICs I mentioned. "Richard" wrote in message ... Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. |
#6
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In article , "Richard"
writes: Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. Yes, you CAN find the parts...those that survive after the 20 to 30 year period from their new introduction until now. The MC3362 is a one-chip FM receiver package available from Kits and Parts. Just add the dual IF filters and support passives, perhaps a power audio IC for more sound, maybe an RF stage for maximum sensitivity. Dieter has a datasheet available for download on it if you like. Problem is that few of those old ICs survive. They didn't sell well enough to support continued production. Hundreds of IC designs have met that fate, were successful, were produced, were sold. They just didn't sell enough. A few were sold off to other semi makers (Fairchild got all of the old National Semi digital line, for example...ON Semi got some of the old Motorola ICs). About three "independent" semi makers in the USA exist as second sources for old, obsolete semiconductors, including specialty ICs. The old RCA Sommerville works and their mighty CMOS line of both digital (CDxxxx) and analog (CAxxxx) got partially picked up by Harris when RCA was sold to GE, but then Harris sold off most of those to others, including Intersil and a few to Maxim (according to part numbers and description). What you, me, and many other hobbyists have to face is that the scene in semiconductor ICs is CHANGING. There exist (and have existed for at least a decade) "foundry" services to allow designs of complex ICs that may be the entirety of a new electronic project. Those won't even appear on the distributor market, just single purchase lot of 100,000 or so, made, installed, and in a successful product only to be succeeded by a changed, more competitive device. You CAN find out much with the right search words, including old part numbers. Unfortunately, many of those old parts have become "unobtainium" and exist only in archival datasheet records. A few remain: MC3362, a one-chip FM receiver; SA602 and SA612 Gilbert cell RF mixers; MC1350 low-VHF differential amplifier; several LMxxx audio devices from National; MC145151 parallel-load PLL all-in-one; CD4046 phase-freq detector for PLLs; 555 timers. The venerable 741 op-amp has long since been replaced by several general purpose op-amps still produced by several makers. Many CDxxxx CMOS digital devices are still available at very low prices (Jameco) and a few CAxxxx analog CMOS are still there. Outside of the Heathkits at the last decade of their existance, I doubt you will find much in the way of articles and "plans" for a homebuilt AM/FM receiver. When the already-manufactured article costs less than the collection of parts needed to build one, why bother? :-) If you want to build a special version for yourself, there's a heaping glob of appnotes and datasheets for available components on the web...but then you have to DESIGN something (true homebrew) instead of copying someone else's design. Len Anderson retired (from regular hours) electronic engineer person |
#7
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In article , "Richard"
writes: Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. Yes, you CAN find the parts...those that survive after the 20 to 30 year period from their new introduction until now. The MC3362 is a one-chip FM receiver package available from Kits and Parts. Just add the dual IF filters and support passives, perhaps a power audio IC for more sound, maybe an RF stage for maximum sensitivity. Dieter has a datasheet available for download on it if you like. Problem is that few of those old ICs survive. They didn't sell well enough to support continued production. Hundreds of IC designs have met that fate, were successful, were produced, were sold. They just didn't sell enough. A few were sold off to other semi makers (Fairchild got all of the old National Semi digital line, for example...ON Semi got some of the old Motorola ICs). About three "independent" semi makers in the USA exist as second sources for old, obsolete semiconductors, including specialty ICs. The old RCA Sommerville works and their mighty CMOS line of both digital (CDxxxx) and analog (CAxxxx) got partially picked up by Harris when RCA was sold to GE, but then Harris sold off most of those to others, including Intersil and a few to Maxim (according to part numbers and description). What you, me, and many other hobbyists have to face is that the scene in semiconductor ICs is CHANGING. There exist (and have existed for at least a decade) "foundry" services to allow designs of complex ICs that may be the entirety of a new electronic project. Those won't even appear on the distributor market, just single purchase lot of 100,000 or so, made, installed, and in a successful product only to be succeeded by a changed, more competitive device. You CAN find out much with the right search words, including old part numbers. Unfortunately, many of those old parts have become "unobtainium" and exist only in archival datasheet records. A few remain: MC3362, a one-chip FM receiver; SA602 and SA612 Gilbert cell RF mixers; MC1350 low-VHF differential amplifier; several LMxxx audio devices from National; MC145151 parallel-load PLL all-in-one; CD4046 phase-freq detector for PLLs; 555 timers. The venerable 741 op-amp has long since been replaced by several general purpose op-amps still produced by several makers. Many CDxxxx CMOS digital devices are still available at very low prices (Jameco) and a few CAxxxx analog CMOS are still there. Outside of the Heathkits at the last decade of their existance, I doubt you will find much in the way of articles and "plans" for a homebuilt AM/FM receiver. When the already-manufactured article costs less than the collection of parts needed to build one, why bother? :-) If you want to build a special version for yourself, there's a heaping glob of appnotes and datasheets for available components on the web...but then you have to DESIGN something (true homebrew) instead of copying someone else's design. Len Anderson retired (from regular hours) electronic engineer person |
#8
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I read in sci.electronics.design that Richard nearlynews_email@ntlworld
..com wrote (in ) about 'Were IC's ever etensively employed in AM/FM RX homebrew projects?', on Sun, 28 Dec 2003: Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. They are not so easy to obtain in small quantities. They were aimed at high-volume consumer product manufacturers. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#9
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I read in sci.electronics.design that Richard nearlynews_email@ntlworld
..com wrote (in ) about 'Were IC's ever etensively employed in AM/FM RX homebrew projects?', on Sun, 28 Dec 2003: Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. They are not so easy to obtain in small quantities. They were aimed at high-volume consumer product manufacturers. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#10
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"Richard" wrote in
: Although I have been interested an amateur radio for about 30 years, I've never focused much attention on radios made with ICs. Lately I have got an interest in FM receivers, and have discovered some FM-related IC's/chipsets. ICs such as LA1177, LA1266, LM7000, (these three being a chipset), and LA1235 etc etc. But, doing a web search , you cannot find any homebrew AM/FM RX using these IC's. Why is this? I would have though they would be ideal for the hobbyist to mess around with. In the early 1970s, the electronics rags were loaded with IC projects. The problem is that those ICs haven't been made since the early 1970s. A tube never changes. I can buy a 6BA6 and buld the same RF amp that was being built in the 1950s and 60s. I can substitute a 6AU6 and it will still work. I can use transistors and do the same thing. An IC has internal "wiring" that is specific to it alone. If you can't get that particular IC, you can't build the project. |
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