Re: LF: exciter for 137 and 500 kHz

[Andy Talbot <andy.g4jnt@googlemail.com>]

Hi Xtian -

 

No need, tnx.

A copy arrived just now from another bad boy :-)

 

Andy
www.g4jnt.com

On 7 November 2010 11:43, Jean-L. RAULT <f6agr@wanadoo.fr> wrote:

Andy

Christian is a bad boy  :o)

I'll scan and forward you tomorrow the english version of the DB2NP's article

Jean-Louis F6AGR






Le 07/11/2010 12:33, Andy Talbot a écrit :

yes please.  

 

May even help my rusty - learnt-at-evening-class German

Andy
www.g4jnt.com

On 7 November 2010 10:54, cricri <cricri.f1vl@wanadoo.fr> wrote:

Hello Andy ,
I'll send you a copy of the german UKW version  !

If you need it . Says and I do  !


Formulas are same ... :-) :-) :-)

73


Xtian / F1VL


Le 07/11/2010 11:03, Andy Talbot a écrit :

Nice little prog - I'd love to see the source code :-)

 

Taken from that reference :-

"The calculations to derive the time constants and therefore the 90 degree frequencies, and the component values, were based on equations in the article by Dr. (Eng) Ralph Oppelt, DB2NP, published in VHF Communications Volume No. 18, Summer, 2/1987."

Does anyone have back copies of VHF Comms ???

Andy
www.g4jnt.com

On 7 November 2010 03:59, <jrusgrove@comcast.net> wrote:

Andy

 

It's been a while ... but believe I used this online calculator.

 

http://www.werewoolf.org.je/apf.htm

 

Jay

 

 

----- Original Message -----

From: Andy Talbot

To: rsgb_lf_group@blacksheep.org

Sent: Saturday, November 06, 2010 9:59 AM

Subject: Re: LF: exciter for 137 and 500 kHz

Very Interesting.  

Where did you find the design data for the allpass network?   I've only been able to find the values for up to 3+3 allpass stages.

 

Mind you, at that number of chips a DSPic begins to look attractive.

 

Andy
www.g4jnt.com

On 6 November 2010 11:52, <jrusgrove@comcast.net> wrote:

Nothing earth shattering ... another way to skin the cat. The 137 and 500 kHz units have been in use for a few years ... just now getting around to the write up.

http://www.w1vd.com/137-500Phasingexciter.html

Jay W1VD  WD2XNS  WE2XGR/2