It would be great to get someone over with an analyzer. You can also
do some SWR checks across both 40 and 15 meters to see what is up.
Tuners out of line.
I think if you are resonant high up in the 40 meter band, you will be
out of band on 15. There is a third harmonic resonance, which is why 40
and 15 line up. If your 40 meter dipole is resonant at 7.100, then
times 3 will put you at 21.300. Right in the middle of the phone
portion of 15. On the other hand, if 40 meters is resonant at 7.250,
then times 3 puts you at 21.750, (out of band).
If this is the problem, you may have to tinker/compromise on 40 meter
resonance to get 15 meters in band.
This is a popular antenna. I would wonder what Alpha Delta says about
15 meter performance. I would probably do SWR plots and get the
analyzer info before contacting them.
73 Steve KW3A
On 10/27/2013 10:11 PM, Tom Behler wrote:
> Steve:
>
> I guess that's what confuses me a bit with the 15-meter portion of my Alpha
> Delta DXCC.
>
> The thing works so well on 40, that you would think it should perform well
> on 15 meters too, especially if it uses the 40 meter part of the antenna to
> tune on 15.
>
> A good friend of mine has an MFJ antenna analyzer, so I may ask him to come
> over here and see where the antenna actually resonates on 15 meters.
>
> That hopefully should tell me something.
>
> Tom Behler: KB8TYJ
>
> ----- Original Message -----
> From: "Steve Forst" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, October 27, 2013 10:04 PM
> Subject: Re: 10 and 15 meters continued
>
>
>> Tom,
>>
>> Sounds like you had fun. Svalbard is between the Top of Norway and the
>> North Pole. It belongs to Norway, but is far enough away so it counts
>> as a separate DXCC country. I don't see them very often, but did work
>> them a few weeks ago in the WAE SSB contest.
>>
>> I did a little bit of S and P this weekend, mostly on Saturday. A
>> number of JA's on 10 and 15, Guam and Ascension island on 15, and 2
>> from Kazakhstan and also the persian Gulf on 10 meters in the morning.
>> Didn't hear anything on 160, but the higher bands were so good, it
>> didn't matter.
>>
>> As for your antenna on 15 meters: If I'm not mistaken, it's full size
>> on 40, loaded for 75/80, and has 2 parallel dipoles for 10 and 20
>> meters. I think the idea is that since 40 and 15 meter bands are
>> harmonically related, there is no "real" 15 meter section, and so you
>> tune the 40 meter part on 15.
>>
>> If the performance is that poor, maybe you can rig up a single band 15
>> meter dipole somewhere.
>>
>> 73, Steve KW3A
>>
>>
>> On 10/27/2013 9:29 PM, Tom Behler wrote:
>>> Hi, again, all.
>>>
>>> Most of the contacts I mentioned were on 10 and 20 meters.
>>>
>>> For some reason, which I'm going to have to investigate, my DXCC tunes,
>>> but
>>> doesn't seem to get out quite as well as I think it should on 15 meters.
>>>
>>> Tom Behler: KB8TYJ
>>>
>>>
>>>
>>
>
>
>
|
