| Home |
| Search |
| Today's Posts |
|
#1
April 29th 04, 12:47 AM
|
|||
|
|||
ladder filters
I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99).
Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#2
April 29th 04, 11:42 AM
|
|||
|
|||
|
See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST
and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message . .. I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#3
April 29th 04, 11:42 AM
|
|||
|
|||
|
See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST
and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message . .. I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#4
May 1st 04, 10:33 PM
|
|||
|
|||
|
Ken,
While rummaging through my archives, I found a link to the articles I referenced. Let me know if you want them. Joe W3JDR "W3JDR" wrote in message ... See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message . .. I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#5
May 1st 04, 10:33 PM
|
|||
|
|||
|
Ken,
While rummaging through my archives, I found a link to the articles I referenced. Let me know if you want them. Joe W3JDR "W3JDR" wrote in message ... See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message . .. I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#6
May 2nd 04, 01:47 AM
|
|||
|
|||
|
W3JDR wrote:
Ken, While rummaging through my archives, I found a link to the articles I referenced. Let me know if you want them. Joe W3JDR I don't seem to have either QST in my collection (there are a few years from 1980-1983 I'm missing). So yes thanks! "W3JDR" wrote in message ... See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message t... I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#7
May 2nd 04, 01:47 AM
|
|||
|
|||
|
W3JDR wrote:
Ken, While rummaging through my archives, I found a link to the articles I referenced. Let me know if you want them. Joe W3JDR I don't seem to have either QST in my collection (there are a few years from 1980-1983 I'm missing). So yes thanks! "W3JDR" wrote in message ... See "Ladder Crystal Filter Design", by J. A. Hardcastle, November 1980, QST and "A Unified Approach to the Design of Crystal Ladder Filters", by Wes Hayward, May 1982, QST. Joe W3JDR "Ken Scharf" wrote in message t... I just got a deal on ebay for 8.3886 mhz crystals (414 pcs for $9.99). Should be able to make a few good ssb and cw filters out of that! They look like std microprocessor types (hc49/u holders) though this isn't a common microprocessor frequency. Guess I'll start with 100pf coupling caps, any good guess on what the termination resistance might be? (I'm looking for a bw suitable for ssb, probably about 2.1khz). Hope this frequency doesn't have any bad mixer products (but I can always pick either high or low side injection if necessary). |
|
#8
May 2nd 04, 06:06 PM
|
|||
|
|||
|
On Sat, 01 May 2004 20:47:10 -0400, Ken Scharf wrote:
I don't seem to have either QST in my collection (there are a few years from 1980-1983 I'm missing). So yes thanks! http://www.cqham.ru/ftp2/QST78_82LadderFlr.djvu 73, Ed. EI9GQ. -- Remove 'X' to reply by E-mail. Linux 2.6.5 |
|
#9
May 2nd 04, 06:06 PM
|
|||
|
|||
|
On Sat, 01 May 2004 20:47:10 -0400, Ken Scharf wrote:
I don't seem to have either QST in my collection (there are a few years from 1980-1983 I'm missing). So yes thanks! http://www.cqham.ru/ftp2/QST78_82LadderFlr.djvu 73, Ed. EI9GQ. -- Remove 'X' to reply by E-mail. Linux 2.6.5 |
| Reply |
| Thread Tools | Search this Thread |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Forum | |||
| Ladder line question ???? | Antenna | |||
| ladder filters | Homebrew | |||
| Ladder Line question please? | Boatanchors | |||
| ladder filters | Homebrew | |||
| Ladder Line or Coax For Reception only? | Antenna | |||
Linear Mode
