Hooking a longwire to an SDR-IQ?

[datainmotion]

While I have been very satisfied with my Alpha-Delta Sloper on my SDR, I'm ready to experiment. I'm thinking of taking some 16 ga. insulated wire and running 100'-200' of it outside (possibly along the top of the stockade fence) for a longwire. What is the best way to connect it, considering the SDR-IQ has only a BNC antenna connection?

 

[ka3jjz]

Run your random wire (really it's not a longwire...) into a 9:1 transformer, make a jumper between the transformer (likely a PL259) to a BNC and you're done...best regards..Mike

 

[datainmotion]

Run your random wire (really it's not a longwire...) into a 9:1 transformer, make a jumper between the transformer (likely a PL259) to a BNC and you're done...best regards..Mike

Nomenclature duly noted

I will start doing some searching for 9:1 transformers. Thanks as always Mike!

 

[Alliance01TX]

SDR Antenna

Hi

I use a 'BNC to Banana' connector (just check online) or for a little more get a Balun type connector with BNC-Banana conector to give you a 50 Ohm connection. I have used both and great results....typically around $10-15. max and if you have a local electronics shop,likely much cheaper.

Have used on my Alfa-Delta via 259-to-BNC connector as well....

As you likely know already, just insure no Transmiters are near the SDR-IQ Antenna or you can damage the unit, per the instructions,etc...

Thx

Bill

 

[datainmotion]

So I'm reading that a balun may "supress" local electrical noise as well? What is the possibilty that it might suppress electrical noise from an alternator?

 

[ka3jjz]

Hmm...if we're talking a typical car alternator, you can buy a kit (I think it has a transformer and a rather large electrolytic) for that...

Anyway these 2 articles from our wiki might prove helpful -

Antenna Transformer Construction and Testing

MØUKD - 9:1 Magnetic Longwire Balun ? - UnUn !

best regards..Mike

 

[Murstech]

Poke the wire into the hole in the middle of the connector and use duck tape to hold it in place!

 

[datainmotion]

Poke the wire into the hole in the middle of the connector and use duck tape to hold it in place!

Can't find the darned duct tape :roll::lol:

 

[majoco]

That's a 9:1 impedance matching transformer, so it's only a 3:1 ratio.

I have about 66ft of wire over the roof into a homemade un-un of a FT43-50 core with 33 turns on the primary and 11 on the secondary - the other side of the primary goes to an earth spike under the antenna. The secondary is hardwired to the coax to the receiver. There is no connection at the un-un for the shield of the coax to ground - that keeps quite a bit of noise out. Works well.