[ARC5] Strange signal on ~3595 kHz

[howard holden]

The July 1980 QST has an article on simple loop direction finders, both 
open wound and ferrite bar. Back in the 80s I built one for 75M using a 
ferrite rod with coil and cap for tuning,  and a sense antenna to give 
the received signal a cardioid pattern, when a numbers CW station often 
came on an early morning net I participated in. I and another fellow 
determined by triangulation that the station was in Cuba, thus ending 
our pursuit. Was pretty simple, but as long as the signal you're hunting 
can be heard, crude location can be determined.


Howie WB2AWQ

On 1/4/2019 10:32 AM, Richard Knoppow wrote:
> Any sort of loop will work, the Adcock is really a sort of loop. Since 
> great precision is not needed a small loop would do. Its a matter of 
> getting readings from a number of separated stations and plotting 
> them. I would give at least an approximate location. At higher 
> frequencies a beam antenna could be used but at 4 Mhz a beam is too 
> large but a loop is quite practical.
>    If a fairly large number of stations hear the signal plotting 
> relative strength might also give a clue as would daytime vs: night 
> time strength. All crude but might at least tell if it were coming 
> from the U.S. or somewhere else.
>
> On 1/4/2019 10:24 AM, Kenneth G. Gordon wrote:
>> On 3 Jan 2019 at 20:45, Richard Knoppow wrote:
>>
>>>      3J would be China but Q has always been reserved for
>>> operating signals (Q signals) so there are no call signs
>>> beginning with Q. Probably not real signs. Be interesting if
>>> anyone with directional antennas could get a fix on it and
>>> triangulate with someone else.
>>
>> Wouldn't that sort of DFing require an Adcock array?
>>
>> Ken W7EKB
>>
>