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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 |
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