[RX320] RX-320D and the H-800 active antenna

[paul]

Dear Frank

thanks for your great contribution here

thanks for indicating where other hards parts can be obtained

looks like an excellent design with the JFET in the front end

again you may want to look at my comments re a whip

maybe applied to other antenna circuits, it could be even better

very best

Paul

Frank Gentges wrote:

>Hi,
>
>Its really not all that hard to build when you see our follow up 
>material. Some of the follow up material makes it easier. My first 
>full-up model is still up on my roof working just fine. Go to the AMRAD 
>web site where we have this follow up material on this antenna and read 
>the FAQ and parts lists.. See
>
>http://www.amrad.org/projects/lf/actant/index.htm
>
>If you are not buried in the midst of high power AM stations you can 
>probably go with the J310 JFET and use 12 volts for the power. That 
>eliminates the heat sink and the very special transistor. In addition, 
>try a longer whip like 6 or 7 feet. The longer whip will improve the HF 
>performance but may introduce too much signal in the AM BC band and 
>cause intermodulation. At least it is worth a try.
>
>We selected a Signal power transformer and they have since decided not 
>to sell single units to experimenters. Another company stepped forward 
>that is willing to do this and we have them in the parts list.
>
>The Amidon cores are available from Bytemark at
>
>http://www.bytemark.com/
>
>Those are really high permeability cores and you really do need them for 
>the low frequency coverage. Don't forget to get an extra core and you 
>can modify your RX320 for LF and VLF. See
>
>http://www.amrad.org/projects/lf/rx/RX320LFMod.pdf
>
>We tested 3 modified RX320s and found the modification actually improved 
>performance slightly at the 10-30 MHz end of the range. We dis not 
>observe reduced performance as some have mentioned.
>
>With all these changes the antenna all goes together about the same as 
>the original article. With the modified RX320 you will have so much 
>signal in the LF/VLF range that you will need a 10 or 20 dB attenuator 
>in front of the RX320 to keep the AGC from pumping badly when you are 
>tuned down there.
>
>Frank K0BRA
>
>Joe Strain wrote:
>
>  
>
>>It's not easy to build. Some parts (a coil or a
>>transformer iirc) are expensive and hard to get. I
>>have been accumulating parts for the da*n thing for
>>years. i gave up and got the best commercial
>>equivalent and found it an amzing antenna beating all
>>my previous stealth and slinky antennas for apartment
>>use
>>
>>http://www.northcountryradio.com/Published/actant_0896/page1.htm
>>
>>cost is less than $50.00 has been in service here for
>>some time and it's a excellent product
>>
>>Yodar
>>
>>--- Tim Heasman <tim at sideswiper.plus.com> wrote:
>>
>> 
>>
>>    
>>
>>>Hi all,
>>>
>>>I just found this file whilst looking up active
>>>antennas.  It looked quite interesting.
>>>
>>>http://www.arrl.org/tis/info/pdf/0109031.pdf
>>>
>>>Happy New Year
>>>
>>>Tim
>>>gm4lmh
>>>
>>>[Non-text portions of this message have been
>>>removed]
>>>
>>>
>>>   
>>>
>>>      
>>>
>>
>>		
>>__________________________________________ 
>>Yahoo! DSL – Something to write home about. 
>>Just $16.99/mo. or less. 
>>dsl.yahoo.com 
>>
>>
>>
>>
>>Yahoo! Groups Links
>>
>>
>>
>>
>>
>>
>>
>> 
>>
>>    
>>
>
>
>
> 
>Yahoo! Groups Links
>
><*> To visit your group on the web, go to:
>    http://groups.yahoo.com/group/RX320/
>
><*> To unsubscribe from this group, send an email to:
>    RX320-unsubscribe at yahoogroups.com
>
><*> Your use of Yahoo! Groups is subject to:
>    http://docs.yahoo.com/info/terms/
> 
>
>
>
>
>  
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://amrad.org/pipermail/tacos/attachments/20060102/69912542/attachment.htm