Filters - Revision history

M0YDH: /* Interdigital filters */ VK3UM software new location

2019-11-16T18:15:30Z

Interdigital filters: VK3UM software new location

2017-09-21T10:28:58Z

Filters for each band

2017-09-14T18:55:12Z

Filters for each band

2017-05-27T07:50:28Z

Building filters

2017-05-27T07:50:03Z

Building filters

2017-05-27T07:47:39Z

Building filters

2017-05-27T07:44:50Z

Combline filters

2017-05-27T07:44:18Z

Combline filters

2017-05-27T07:42:46Z

Building filters

2017-05-27T07:42:10Z

Building filters

@@ Line 45: / Line 45: @@
 Interdigital filters are not, as their name suggests, digital filters but very high Q filters which normal are used for bandpass filters and they are quite easy to construct if you have any metalworking skills.
 If you want to design one from scratch Doug, VK3UM, now sadly Silent Key, has a calculator http://www.vk3um.com/interdigital%20filter.html.
 Jim KH6HTV has an interesting paper on his [https://kh6htv.files.wordpress.com/2011/09/an-22b-inter-digital-bpf.pdf website].

← Older revision		Revision as of 10:28, 21 September 2017
Line 50:		Line 50:

	===Filters for each band===		===Filters for each band===
		+
		+	Anntenae-amplifiers in Serbia do some very nice filter for all bands at reasonable cost: http://www.antennas-amplifiers.com/Band-Pass-Filter

	There's a lot of filter designs available for DIY build or to buy listed on these pages:		There's a lot of filter designs available for DIY build or to buy listed on these pages:

@@ Line 52: / Line 52: @@
 There's a lot of filter designs available for DIY build or to buy listed on these pages:
+*[[70MHz filters]]
 *[[146 MHz filters]]
 *[[70cms filters]]

@@ Line 27: / Line 27: @@
 ===Building filters===
-Sharp filters can not be made using surface mount components on a PCB.  However, good filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
+Sharp filters can not be made using surface mount components on a PCB!  However, good filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
 ===Combline filters===

@@ Line 27: / Line 27: @@
 ===Building filters===
-Unfortunately, sharp filters can not be made using surface mount components on a PCB.  However, good filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
+Sharp filters can not be made using surface mount components on a PCB.  However, good filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
 ===Combline filters===

@@ Line 27: / Line 27: @@
 ===Building filters===
-Reasonable filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
+Unfortunately, sharp filters can not be made using surface mount components on a PCB.  However, good filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
   A great place to start if you fancy building your own is W1GHZ paper on making combline filters from an Altoid's tin (any other metal tin will do) - http://www.w1ghz.org/filter/Altoids_Tin_Filters.pdf
@@ Line 36: / Line 40: @@
 [http://www.w1ghz.org/filter/Combline_Filters_for_VHF_and_UHF.pdf Another interesting paper by Paul] with some simple practical combline designs, this time made in the standard Hammond Diecast boxes - these are high performance band pass filters designed to cure the problems when using wide band pre-amps - as illustrated at the top of this page!
 ===Interdigital filters===

← Older revision		Revision as of 07:44, 27 May 2017
Line 34:		Line 34:

	[[File:432 combline.JPG\|200px]]		[[File:432 combline.JPG\|200px]]
−
−	~~===Combline filters===~~

	[http://www.w1ghz.org/filter/Combline_Filters_for_VHF_and_UHF.pdf Another interesting paper by Paul] with some simple practical combline designs, this time made in the standard Hammond Diecast boxes - these are high performance band pass filters designed to cure the problems when using wide band pre-amps - as illustrated at the top of this page!		[http://www.w1ghz.org/filter/Combline_Filters_for_VHF_and_UHF.pdf Another interesting paper by Paul] with some simple practical combline designs, this time made in the standard Hammond Diecast boxes - these are high performance band pass filters designed to cure the problems when using wide band pre-amps - as illustrated at the top of this page!

@@ Line 37: / Line 37: @@
 ===Combline filters===
-[http://www.w1ghz.org/filter/Combline_Filters_for_VHF_and_UHF.pdf A very interesting paper by Paul Wade] with some simple practical designs made in the standard Hammond Diecast boxes of some high performance band pass filters designed to cure the problems when using wide band pre-amps - as illustrated at the top of this page!
+[http://www.w1ghz.org/filter/Combline_Filters_for_VHF_and_UHF.pdf Another interesting paper by Paul] with some simple practical combline designs, this time made in the standard Hammond Diecast boxes - these are high performance band pass filters designed to cure the problems when using wide band pre-amps - as illustrated at the top of this page!
 These are easy to make than interdigital skills and anyone with reasonable drill and hacksaws skills can make them.

@@ Line 29: / Line 29: @@
 Reasonable filters are actually quite easy to build with just a medium weight soldering iron and tin snips!
-  A great place to start if you fancy building your own is W1GHZ paper on making filters from an Altoid's tin (any other metal tin will do) - http://www.w1ghz.org/filter/Altoids_Tin_Filters.pdf
+  A great place to start if you fancy building your own is W1GHZ paper on making combline filters from an Altoid's tin (any other metal tin will do) - http://www.w1ghz.org/filter/Altoids_Tin_Filters.pdf
 The 432 MHz combline filter in a metal tin is really easy to build and would make a really good rx filter for 70cms - put after your wideband SPF5043 or PGA103 pre-amp and before your tuner input.