External Antenna For Grundig G5

[ssbothwell SWL]

i've had a grundig G5 for about a year now and have never really been satisfied with it on anything but broadcast band radio. I rarely get anything in the shortwave bands.

Today i decided to try attaching a long wire antenna to see if it would improve my reception. I cut a 33foot length of 18awg stranded copper wire and attached one end to a tree in my backyard. On the other end i soldered a minijack connector that fits the external antenna jack on the G5.

To my shock and dismay I actually got worse reception with the long wire antenna than with the stock telescoping antenna. i didn't bother grounding the receiver, but then again i also haven't bothered grounding it with the stock telescoping antenna. why would a long wire perform worse than a ~2ft telescope?

At this point i dont want to invest time into a fancy antenna array for this receiver but there must be a way to make it more useful for hambands and general swl. any suggestions?

[Pete, WA2CWA]

The manual indicates external antenna should connected with 50/75 coax cable.

Make sure DX/local switch is set to DX.
Make sure plug, after soldering, is not shorted. i.e. minute solder bridge
If possible check the antenna jack.
Try connecting the long wire, directly to the antenna on the radio, but don't extend the anenna when doing the test.

And some G5 discussion that might be helpful: http://forums.radioreference.com/hf-mw-lw-general-discussion/182246-grundig-g5-newb-s.html

[ssbothwell SWL]

well i'm embarrassed to say i accidentally had some strands of wire shorting the signal and ground leads in to minijack connector. the antenna is working _much_ better now. l added a connection to earth ground and that helped as well. 

[kb3ouk]

my grundig s350 (the original verison, not the deluxe) seems to act worse when i have an external antenna on it, i can't remember if i had an external antenna and had it grounded, but i do remember grounding it even with th ebuilt in antenna didn't improve it that much, and trying to have an external antenna without it grounded overloads it badly.

[Pete, WA2CWA]

Sometimes to address the issue of overload when connecting an external antenna, the use of a tuner and/or a step attenuator between the antenna and radio helps. Having a variable RF gain control or at least a "DX/Local" switch can also help the issue. When replacing an existing telescoping-type antenna on a receiver, sometimes users opt for a longer one (i.e. longer should be better) and find reception is not as good because they didn't do a realignment of the front-end stage(s) with the new replacement antenna.

[kb3ouk]

witht the rf gain knob on the s350, there are basically two settings: overload or nothing. its labeled i think 0 to 10, but only really changes any between 0 and 3, 3 to 10 is all the same, no change.

[ssbothwell SWL]

as far as i can tell my G5 doesn't have an rf gain control other than the DX/Local switch. It also doesn't have a labelled ground point.

Here is how i am trying to setup my antenna. any comments would be appreciated:

1. I have a 33foot 18awg copper wire running from a tree to the roof of my house.
2. I have a grounding pole setup next to my house and directly below the point on my roof where the antenna is mounted.
3. I have a second 18awg  copper wire running up from the grounding wire to the roof where my antenan terminates.
4. I have both these wires soldered onto a RG6 coaxial socket.
5. I plan to install an RG6 coaxial (it is the only kind of coaxial I have on hand) cable from the roof down to a window on the first floor where I will run it indoors.
6. I plan to put a coaxial -> minijack adapter on the RG6 so I can connect antenna and ground into the grundig G5.

Is this an acceptable way to hookup an end fed antenna and to properly ground my receiver? Is the long wire from earth ground to the coaxial line going to turn it into a badly tuned dipole?

Do I want to use a 9:1 (or some other ratio) balun such as this http://www.bobsamerica.com/9-1balun.html ?

thanks for the help.

[KA2DZT]

The right way to do it is to just run the #18 from the antenna down the side of the house and try to run it in to the receiver.  Your ground wire can run in also.  Ground wires need to be as short as possible.  If your receiver runs off AC power it is probably grounded through the AC line.  Adding another ground from a separate ground rod can cause problems and should be avoided.  You can ground to a water pipe if one is nearby.

If your receiver only runs from batteries then you can use a separate ground rod or a water pipe ground

Running a ground wire up to the roof to connect to the "F" connector will really work like a dipole with one end grounded.

Fred

[kb3ouk]

if it's like the grundig i have, it's powered off a wall wart.

[Pete, WA2CWA]

Most of these types of portables are not great communication type receivers. The G5 sells for $100 to $150 depending on where you buy and cost to manufacture is probably under $50. The external antenna port on the G5 will only work for FM and SW. The SW section consists of wide band RF amplifier with no tuned circuits. With an external antenna and no external controls, chance of front end overload with strong signals is not uncommon. Selectivity of these portables is marginal at best. Several manufacturers make internal and external active antennas that generally are used with portables to add additional controllable sensitivity and gain. AMECO makes a nice one, http://www.universal-radio.com/catalog/preamps/1512.html and there are a number of others on the market.

[kb3ouk]

direct conversion receivers, like what my grundig's shortwave section is, are not the greatest. anybody make a good portable superheterodyne shortwave set anymore?

[ssbothwell SWL]

i hung the antenna from my roof to a tree in order to try to get better reception and to make it less noticeable in my backyard. if i had it going from the tree into a first floor window (where my radio gear is stored) would make the antenna hang really low.

i suppose i could just cut an even longer wire and have it go from the tree to my roof and then route it down the side of the house to my window. with a receiver such as the G5, should i even bother worrying about the getting a precise length and minimizing bends and kinks in it?

[kb3ouk]

i hung the antenna from my roof to a tree in order to try to get better reception and to make it less noticeable in my backyard. if i had it going from the tree into a first floor window (where my radio gear is stored) would make the antenna hang really low.

i suppose i could just cut an even longer wire and have it go from the tree to my roof and then route it down the side of the house to my window. with a receiver such as the G5, should i even bother worrying about the getting a precise length and minimizing bends and kinks in it?

no, just get the wire in the air and that's it. i wouldn't be too concerned with the length or any kinks in the wire.

[KA2DZT]

i hung the antenna from my roof to a tree in order to try to get better reception and to make it less noticeable in my backyard. if i had it going from the tree into a first floor window (where my radio gear is stored) would make the antenna hang really low.

i suppose i could just cut an even longer wire and have it go from the tree to my roof and then route it down the side of the house to my window. with a receiver such as the G5, should i even bother worrying about the getting a precise length and minimizing bends and kinks in it?

Your right, just get up some wire from the tree to the roof and then run it down the side of the house.  The length can be whatever.  You should be using some type of insulators at the tree and roof ends.

Don't worry about wires in the backyard, it gives a place for birds to sit.  And remember, you're just getting started.  Before long, you'll have wires and cables hanging everywhere.

Fred