[600MRG] WE2XGR/1 513.5 CW On Ground Dipole ***New Balun ****

[Marshall Cross]

Frank, efficiency estimates were not pie in the sky but based on NEC 4.2 modeling using conductivity measurements made using E/H Geonics set at 490 kHz and field strength measurements using calibrated FSM. I am a graduate EE and PE with 51 years experience with radio system engineering so I don't do pie in the sky estimates. Marshall, W1HK 

Sent from my iPhone

> On Oct 9, 2015, at 4:39 PM, Frank Lotito <k3dz at live.com> wrote:
> 
> Warren - Your initial balun warming up 16 F over ambient does not seem bad, at least not to me.  However, inferring a better balun by using some else's experimental result which relied on "sky in the pie" guestimates of overall antenna efficiency is way to far out regarding a particular component's efficiency.  Or am I missing something?
> 
> 73 Frank  K3DZ / WH2XHA
> 
> ________________________________________
> From: Warren K2ORS <k2ors at verizon.net>
> Sent: Friday, October 9, 2015 4:28 PM
> To: Frank Lotito
> Subject: Re: [600MRG] WE2XGR/1 513.5 CW On Ground Dipole ***New Balun ****
> 
> Frank,
> 
>     1st balun warmed up by 16F after transmitting for a few hours (this
> was in open air with no enclosure and an average of 25W [actually 50W
> and 50% duty cycle]). New balun was custom made for Marshall W1HK and
> tested by him, his on-ground dipole gave an efficiency of 2.5% (60 W
> from transmitter resulted in 1.5W ERP.
> 
> 73 Warren
> 
> 
>> On 10/9/2015 4:24 PM, Frank Lotito wrote:
>> Warren - When you say "more efficient" balun for your on-the-ground antenna experiments, what do you mean?  The prior balun got red hot and burnt out, while the new design balun only gets slightly warm?
>> 
>> 73 Frank K3DZ / WH2XHA
>> _______________________________________
>> From: 600MRG <600mrg-bounces at w7ekb.com> on behalf of Warren K2ORS <k2ors at verizon.net>
>> Sent: Friday, October 9, 2015 4:15 PM
>> To: Discussion of the Lowfer (US, European, & UK) and MedFer bands; 600MRG
>> Subject: [600MRG] WE2XGR/1 513.5 CW On Ground Dipole ***New Balun ****
>> 
>> Trying the on-ground dipole again, this time with a new and more
>> efficient balun.  CW on 513.5, hopefully far enough away in freq from
>> NDB YWA.
>> 
>>   Reports welcome!
>> 
>> 73 Warren K2ORS
> 
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
> 
> 
> _______________________________________________
> 600MRG mailing list
> 600MRG at w7ekb.com
> http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com
> 
> 
>