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Homebrew crystals for transmitters
Hello, All:
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL |
H. Peter Friedrichs wrote:
Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
H. Peter Friedrichs wrote:
Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
On Mon, 12 Apr 2004 17:41:41 -0700, Tim Wescott
wrote: H. Peter Friedrichs wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. Aw, c'mon, Tim. Photocopy and snail it to the guy! |
On Mon, 12 Apr 2004 17:41:41 -0700, Tim Wescott
wrote: H. Peter Friedrichs wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. Aw, c'mon, Tim. Photocopy and snail it to the guy! |
Paul Burridge wrote:
On Mon, 12 Apr 2004 17:41:41 -0700, Tim Wescott wrote: H. Peter Friedrichs wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. Aw, c'mon, Tim. Photocopy and snail it to the guy! Oh wait! Look -- out there, through that big thing that looks like an aluminum-framed monitor! There's trees! There's a sky! There's smelly old cars putting things into the box on the road by my driveway! It's it's -- the real world! Dang! I forgot about that. Suitably chastised, the respondent offers: If you're interested send me your address, I'll bleach out a few pages worth of my precious vintage ink (you'll see the irony of that when you get the copies), and send you the stuff. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Paul Burridge wrote:
On Mon, 12 Apr 2004 17:41:41 -0700, Tim Wescott wrote: H. Peter Friedrichs wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL "Cutting Quartz Crystal Plates". QST, January 1935, page 36. Unfortunately that's from my swiftly-rotting paper issue, and I don't have a scanner. Aw, c'mon, Tim. Photocopy and snail it to the guy! Oh wait! Look -- out there, through that big thing that looks like an aluminum-framed monitor! There's trees! There's a sky! There's smelly old cars putting things into the box on the road by my driveway! It's it's -- the real world! Dang! I forgot about that. Suitably chastised, the respondent offers: If you're interested send me your address, I'll bleach out a few pages worth of my precious vintage ink (you'll see the irony of that when you get the copies), and send you the stuff. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
"H. Peter Friedrichs" wrote in message ink.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. -- Steve N, K,9;d, c. i My email has no u's. |
"H. Peter Friedrichs" wrote in message ink.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. -- Steve N, K,9;d, c. i My email has no u's. |
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie |
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie |
"Eddie Haskel" ) writes:
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie Actually, considering the date of the magazine, they aren't talking about shifting commercial crystals. They must be talking about taking quartz, and making crystals. On the same level as making your own capacitors. I gather it might have been common back then. Does the date coincide with requirements of "crystal like" stability? I can't remember when such rules came into effect, but I can imagine it would have set off homebrewing of crystals. For that matter, there may not have been that much choice; I have no idea what the state of commercial crystal manufacturers were back then. ANd considering it was the thirties, likely many hams had no money to buy commercial crystals, but they could scrounge. It was WWII that offered up all those surplus crystals in FT-243 holders. If you were lucky, some would fall where you needed them. A bit less luck, and you'd at least find some close enough to your needs that you could grind them a bit and move them onto your frequency. With no luck, you'd have to buy crystals. One could reference the other thread about selecting a receiver's IF frequency. Often, such selection resolved to what was available. If you could buy a filter, you'd use that frequency. Likewise when hams started making crystal lattice filters after WWII, they used frequencies which were available (which luckily overlapped the common 455KHz IF). Even today, the choice of frequency for a homemade crystal ladder filter often depends on what crystals are available cheap. Not the only criteria, but one of the criterias. Michael VE2BVW |
"Eddie Haskel" ) writes:
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie Actually, considering the date of the magazine, they aren't talking about shifting commercial crystals. They must be talking about taking quartz, and making crystals. On the same level as making your own capacitors. I gather it might have been common back then. Does the date coincide with requirements of "crystal like" stability? I can't remember when such rules came into effect, but I can imagine it would have set off homebrewing of crystals. For that matter, there may not have been that much choice; I have no idea what the state of commercial crystal manufacturers were back then. ANd considering it was the thirties, likely many hams had no money to buy commercial crystals, but they could scrounge. It was WWII that offered up all those surplus crystals in FT-243 holders. If you were lucky, some would fall where you needed them. A bit less luck, and you'd at least find some close enough to your needs that you could grind them a bit and move them onto your frequency. With no luck, you'd have to buy crystals. One could reference the other thread about selecting a receiver's IF frequency. Often, such selection resolved to what was available. If you could buy a filter, you'd use that frequency. Likewise when hams started making crystal lattice filters after WWII, they used frequencies which were available (which luckily overlapped the common 455KHz IF). Even today, the choice of frequency for a homemade crystal ladder filter often depends on what crystals are available cheap. Not the only criteria, but one of the criterias. Michael VE2BVW |
On Mon, 12 Apr 2004 21:29:32 GMT, "H. Peter Friedrichs"
wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL ============================ Here's a few more pointers: CQ 01/49 p. 37 Grinding xtals simplified CQ 11/57 p. 74 How to grind xtals CQ 10/65 p. 52 Grinding surplus xtals QST 02/54 p. 45 Using grid-dipper as aid to xtal grinding QST 06/58 p. 19 Grinding xtals Jack W8RAG |
On Mon, 12 Apr 2004 21:29:32 GMT, "H. Peter Friedrichs"
wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL ============================ Here's a few more pointers: CQ 01/49 p. 37 Grinding xtals simplified CQ 11/57 p. 74 How to grind xtals CQ 10/65 p. 52 Grinding surplus xtals QST 02/54 p. 45 Using grid-dipper as aid to xtal grinding QST 06/58 p. 19 Grinding xtals Jack W8RAG |
Michael Black wrote:
"Eddie Haskel" ) writes: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie Actually, considering the date of the magazine, they aren't talking about shifting commercial crystals. They must be talking about taking quartz, and making crystals. On the same level as making your own capacitors. I gather it might have been common back then. Does the date coincide with requirements of "crystal like" stability? I can't remember when such rules came into effect, but I can imagine it would have set off homebrewing of crystals. For that matter, there may not have been that much choice; I have no idea what the state of commercial crystal manufacturers were back then. ANd considering it was the thirties, likely many hams had no money to buy commercial crystals, but they could scrounge. It was WWII that offered up all those surplus crystals in FT-243 holders. If you were lucky, some would fall where you needed them. A bit less luck, and you'd at least find some close enough to your needs that you could grind them a bit and move them onto your frequency. With no luck, you'd have to buy crystals. One could reference the other thread about selecting a receiver's IF frequency. Often, such selection resolved to what was available. If you could buy a filter, you'd use that frequency. Likewise when hams started making crystal lattice filters after WWII, they used frequencies which were available (which luckily overlapped the common 455KHz IF). Even today, the choice of frequency for a homemade crystal ladder filter often depends on what crystals are available cheap. Not the only criteria, but one of the criterias. Michael VE2BVW This was actually just before then, when crystal stability was expected but not (I believe) required. The '33 handbook "starter transmitter" was just a TNT oscillator connected to an antenna. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Michael Black wrote:
"Eddie Haskel" ) writes: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie Actually, considering the date of the magazine, they aren't talking about shifting commercial crystals. They must be talking about taking quartz, and making crystals. On the same level as making your own capacitors. I gather it might have been common back then. Does the date coincide with requirements of "crystal like" stability? I can't remember when such rules came into effect, but I can imagine it would have set off homebrewing of crystals. For that matter, there may not have been that much choice; I have no idea what the state of commercial crystal manufacturers were back then. ANd considering it was the thirties, likely many hams had no money to buy commercial crystals, but they could scrounge. It was WWII that offered up all those surplus crystals in FT-243 holders. If you were lucky, some would fall where you needed them. A bit less luck, and you'd at least find some close enough to your needs that you could grind them a bit and move them onto your frequency. With no luck, you'd have to buy crystals. One could reference the other thread about selecting a receiver's IF frequency. Often, such selection resolved to what was available. If you could buy a filter, you'd use that frequency. Likewise when hams started making crystal lattice filters after WWII, they used frequencies which were available (which luckily overlapped the common 455KHz IF). Even today, the choice of frequency for a homemade crystal ladder filter often depends on what crystals are available cheap. Not the only criteria, but one of the criterias. Michael VE2BVW This was actually just before then, when crystal stability was expected but not (I believe) required. The '33 handbook "starter transmitter" was just a TNT oscillator connected to an antenna. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Eddie Haskel wrote:
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie No, the good _really_ 'ol days of taking a chunk of quartz, whacking pieces off of it with a mud saw, hand lapping the saw marks off and mounting it in a home-made holder. That namby-pamby FT-243 wasn't invented until just before WW-II. The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Eddie Haskel wrote:
Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie No, the good _really_ 'ol days of taking a chunk of quartz, whacking pieces off of it with a mud saw, hand lapping the saw marks off and mounting it in a home-made holder. That namby-pamby FT-243 wasn't invented until just before WW-II. The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
"Tim Wescott" wrote in message ... Eddie Haskel wrote: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie No, the good _really_ 'ol days of taking a chunk of quartz, whacking pieces off of it with a mud saw, hand lapping the saw marks off and mounting it in a home-made holder. That namby-pamby FT-243 wasn't invented until just before WW-II. The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
"Tim Wescott" wrote in message ... Eddie Haskel wrote: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Ah yes..the good 'ol days of grinding FT-243 Xtals with toothpaste(or comet)to go up, and writing on the blank with #2 pencil lead to take them down a few Kilocycles....Eddie No, the good _really_ 'ol days of taking a chunk of quartz, whacking pieces off of it with a mud saw, hand lapping the saw marks off and mounting it in a home-made holder. That namby-pamby FT-243 wasn't invented until just before WW-II. The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
"Tim Wescott" wrote in message ... Eddie Haskel wrote: Yes Mrs. Cleaver... ....Eddie [...snip...] The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... Tim Wescott O U C H !! |
"Tim Wescott" wrote in message ... Eddie Haskel wrote: Yes Mrs. Cleaver... ....Eddie [...snip...] The same magazine has an article about the blind ham who built his own equipment. Soldering by feel. There were giants in those days... Tim Wescott O U C H !! |
actually, it is a lot easier to simply etch or grind away some of the xtal, then check it with a grid dip oscillator for sharp dip, no need to remount and test ;-) An old Hints and Kinks IIRC. This could be really handy if you wanted to make a xtal filter and needed to really match and control the xtal freq offsets (what, 3.5179 Mhz xtals from TV color burst sources?) ;-) and how about drilling a small hold in the holder so you could tread a small bolt to put pressure on the xtal holder plates, shifting the xtal freq. around like a xtal controlled VFO - but only a handful of khz ;-) Still, very solid (pun intended) freq. source that can be varied around enough to avoid QRM at minimal cost and effort for QRPers and so on? ;-) Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) regards bobm -- ************************************************** ********************* * Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 * ********************Standard Disclaimers Apply************************* |
actually, it is a lot easier to simply etch or grind away some of the xtal, then check it with a grid dip oscillator for sharp dip, no need to remount and test ;-) An old Hints and Kinks IIRC. This could be really handy if you wanted to make a xtal filter and needed to really match and control the xtal freq offsets (what, 3.5179 Mhz xtals from TV color burst sources?) ;-) and how about drilling a small hold in the holder so you could tread a small bolt to put pressure on the xtal holder plates, shifting the xtal freq. around like a xtal controlled VFO - but only a handful of khz ;-) Still, very solid (pun intended) freq. source that can be varied around enough to avoid QRM at minimal cost and effort for QRPers and so on? ;-) Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) regards bobm -- ************************************************** ********************* * Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 * ********************Standard Disclaimers Apply************************* |
Steve Nosko wrote:
"H. Peter Friedrichs" wrote in message link.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM |
Steve Nosko wrote:
"H. Peter Friedrichs" wrote in message link.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM |
Bob Monaghan ) writes:
Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW |
Bob Monaghan ) writes:
Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW |
Michael Black wrote:
Bob Monaghan ) writes: Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW Absolutely: You should only make your own crystals for the same reasons you'd knap your own stone tools -- to understand how it was done back in the day, and to have some thing to show off to friends. You could get crystals much faster by cleaning toilets at McDonald's and buying them at $12 a pop than you could making them from scratch. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Michael Black wrote:
Bob Monaghan ) writes: Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW Absolutely: You should only make your own crystals for the same reasons you'd knap your own stone tools -- to understand how it was done back in the day, and to have some thing to show off to friends. You could get crystals much faster by cleaning toilets at McDonald's and buying them at $12 a pop than you could making them from scratch. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
"Bill Janssen" wrote in message ... Steve Nosko wrote: "H. Peter Friedrichs" wrote in message link.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM Sounds important, Bill, but my words may have been misunderstood. By edges I meant the end surfaces...as in ; stand the blank up on one edge - vertically - there are four of 'em. I don't remember if he said that the ends must be made to have a 90 degree angle with the faces or what. I just remember that he said that you grind these sides for best / better activity. I was not referring to the outer reaches of the two large faces as in; is the face flat or curved in some way. -- Steve N, K,9;d, c. i My email has no u's. |
"Bill Janssen" wrote in message ... Steve Nosko wrote: "H. Peter Friedrichs" wrote in message link.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM Sounds important, Bill, but my words may have been misunderstood. By edges I meant the end surfaces...as in ; stand the blank up on one edge - vertically - there are four of 'em. I don't remember if he said that the ends must be made to have a 90 degree angle with the faces or what. I just remember that he said that you grind these sides for best / better activity. I was not referring to the outer reaches of the two large faces as in; is the face flat or curved in some way. -- Steve N, K,9;d, c. i My email has no u's. |
Michael,
I'm interested in "extreme" homebrew for its own sake. I simply like it. http://www.mindspring.com/~pfriedr/b...ry/gallery.htm http://www.mindspring.com/~pfriedr/b...ry/gallery.htm Pete AC7ZL "Michael Black" wrote in message ... Bob Monaghan ) writes: Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW |
Michael,
I'm interested in "extreme" homebrew for its own sake. I simply like it. http://www.mindspring.com/~pfriedr/b...ry/gallery.htm http://www.mindspring.com/~pfriedr/b...ry/gallery.htm Pete AC7ZL "Michael Black" wrote in message ... Bob Monaghan ) writes: Wasn't there a recent historical article in QST on the role of the quartz xtal industry in WWII, how they figured out overtone osc. issues and so on? Given that some sources ask $12 and up for scanner and ham crystals, these costs add up rather fast if you need to replace a bunch of xtals in a scanner. So the search for alternatives seems quite worthwhile ;-) But they already figured out the solution, thirty years ago, and it did not require going to the quarry for quartz and digging out old QSTs. The need for a lot of crystals luckily coincided with digital ICs, so before most people could get around to paying for all the crystals to fill out a mult-channel unit, synthesizers came along so you only needed one crystal. About as soon as it could be done practically, hams built them and wrote up articles in the ham magazines. Anyone who decides to make their own crystals today, other than for the sake of doing so (and I admit it would be an interesting thing to try), will likely find they can't go for the subminiature look, and probably will find that putting effort into building a synthesizer still makes sense if you need more than a few crystals. Michael VE2BVW |
Jack/All
Thanks very much for the tips. I have already decided to purchase the QST's I'm looking for on CDROM. I wonder if CQ offers back issues in electronic format...I'd have to bop over to their web site and see. Pete AC7ZL "J. Yazel" wrote in message ... On Mon, 12 Apr 2004 21:29:32 GMT, "H. Peter Friedrichs" wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL ============================ Here's a few more pointers: CQ 01/49 p. 37 Grinding xtals simplified CQ 11/57 p. 74 How to grind xtals CQ 10/65 p. 52 Grinding surplus xtals QST 02/54 p. 45 Using grid-dipper as aid to xtal grinding QST 06/58 p. 19 Grinding xtals Jack W8RAG |
Jack/All
Thanks very much for the tips. I have already decided to purchase the QST's I'm looking for on CDROM. I wonder if CQ offers back issues in electronic format...I'd have to bop over to their web site and see. Pete AC7ZL "J. Yazel" wrote in message ... On Mon, 12 Apr 2004 21:29:32 GMT, "H. Peter Friedrichs" wrote: Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL ============================ Here's a few more pointers: CQ 01/49 p. 37 Grinding xtals simplified CQ 11/57 p. 74 How to grind xtals CQ 10/65 p. 52 Grinding surplus xtals QST 02/54 p. 45 Using grid-dipper as aid to xtal grinding QST 06/58 p. 19 Grinding xtals Jack W8RAG |
Steve Nosko wrote:
"Bill Janssen" wrote in message ... Steve Nosko wrote: "H. Peter Friedrichs" wrote in message thlink.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM Sounds important, Bill, but my words may have been misunderstood. By edges I meant the end surfaces...as in ; stand the blank up on one edge - vertically - there are four of 'em. I don't remember if he said that the ends must be made to have a 90 degree angle with the faces or what. I just remember that he said that you grind these sides for best / better activity. I was not referring to the outer reaches of the two large faces as in; is the face flat or curved in some way. I understood what you meant. Just never considered that important. Maybe that is something I missed. Bill K7NOM |
Steve Nosko wrote:
"Bill Janssen" wrote in message ... Steve Nosko wrote: "H. Peter Friedrichs" wrote in message thlink.net... Hello, All: Rumor has it that QST featured an article in a January/1930 or January/1935 issue on the subject of homebrew transmitter crystals - how cut, lap, and mount them. If anyone has QST on CDROM for those years, I'd sure appreciate if you could take a look. Remove XXX's and ZZZ's if you wish to reply directly, and thanks. Pete AC7ZL Pete, I have my Dad's grinding stuff, but don't do it. One thing to keep in mind, and I don't know the details, but remember that the crystal activity is effected by the edges. Grinding the edges is one of the more esoteric aspects. The trick isn't the edges but keeping the two surfaces parallel and flat. The procedure is to grind a little and check the activity. If it is down try to grind the center or edges and check again. If it gets better then go back to to grinding and trying to keep it flat. Anyway that is the method I used. Bill K7NOM Sounds important, Bill, but my words may have been misunderstood. By edges I meant the end surfaces...as in ; stand the blank up on one edge - vertically - there are four of 'em. I don't remember if he said that the ends must be made to have a 90 degree angle with the faces or what. I just remember that he said that you grind these sides for best / better activity. I was not referring to the outer reaches of the two large faces as in; is the face flat or curved in some way. I understood what you meant. Just never considered that important. Maybe that is something I missed. Bill K7NOM |
"Bill Janssen" wrote in message ... Steve Nosko wrote: I was not referring to the outer reaches of the two large faces as in; is the face flat or curved in some way. I understood what you meant. Just never considered that important. Maybe that is something I missed. Bill K7NOM Unfortunately, Dad went in the blink of an eye. I'm glad for him, but I didn't have the chance to talk, ask questions or say goodby. -- Steve N, K,9;d, c. i My email has no u's. |
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