On 12/19/2010 6:28 AM, Joe from Kokomo wrote:

...
...and I'll just bet -you- [JS] that you are not familiar with the
concept of "front end overload". More [antenna] is NOT always better.

On 12/19/2010 2:37 PM, John Smith wrote:

Actually, I am, you are quite wrong.

Well, hard to believe that you are familiar with front end overload as
you say; you had at least two posts touting a long antenna, which would
overload the particular radio the OP was asking about.

On 12/19/2010 2:37 PM, John Smith wrote:

However, we can be quite sure you are unfamiliar with narrow filters and
attenuators ... most likely, you don't even own one!

Bzzzzzttt! Wrong again!

Yes, I am familiar with narrow filters and attenuators -- BUT...this was
totally NON-applicable to the receiver the OP was addressing.

Furthermore, once the front end has reached overload, all the downstream
narrow filters in the world won't do any good.

And, yes, I do own a lot of radio stuff, from a 1912 loose coupler
crystal set to vacuum tube ham transmitters and receivers to the latest
solid state ham transceivers to vintage SWL/ham receivers. Heck, some
even have 500 and 250 Hz filters that I use for RTTY and CW contesting.

Regards,
JS

Feel free to have the last word...

Regards and happy holidays,
Joe

On 12/19/2010 12:43 PM, Joe from Kokomo wrote:

...
Feel free to have the last word...

Regards and happy holidays,
Joe

All but the most blatant newbies should be able to deal with a "too good
an antenna."

Because of disinformation and "wives tales", I suspect there are many
with a tiny 30 ft. antenna who think they are realized "good reception"
and feeling quite capable of advising others.

It is simply time to fix this ...

Regards,
JS

On Dec 19, 4:58*am, dave wrote:
Kevin Alfred Strom wrote:
On 12/19/2010 12:00 AM, garrett1415 wrote:
Hey Folks,
I'm Garrett. I'm new here, so I think it'd be appropriate to say hello..
I'm relatively new to the hobby, I recently bought my first shortwave
receiver, a Sony ICF-SW7600GR. I'm living in Michigan currently, and
I'm a Junior in High School.

So here's my questions:
I've been using my receiver with the included whip antenna and the
included portable wire antenna. I've been having trouble picking up
anything at all, even the more powerful stations. Does anyone have any
insight? Should I get an antenna? If so, what kind?

Kevin, WB4AIO.

- Sony used to make a cool folding loop for that radio.

Sony AN-LP1 Active Antenna
http://www.universal-radio.com/catalog/sw_ant/3676.html

- You'd just hang it in a picture window.

As shown on a Window
http://www.universal-radio.com/catal...nt/3676win.jpg

On Dec 19, 11:36*am, John Smith wrote:
On 12/19/2010 4:19 AM, RHF wrote:

...

JS - It is a 'portable' AM/FM Shortwave Radio and
most of them are prone to overload from very long
wire antennas.
...

- That is why attenuators/narrow-filters are used.
-*It is a simple law of physics, long antennas WILL
- receive signals short ones WILL NOT.
-
- No one is saying that you cannot refuse to avail
- yourself of better reception ... some of us just find
- that unacceptable ...
-
- Regards,
- JS

JS,

First a 'portable' AM/FM Shortwave Radio
+plus+
Second a shorter 30~45 Foot Random Wire Antenna

Third = Nothing Extra Required
No Attenuators
No Antenna Tuners
No Pre-Selectors

-wrt- Radio + Antenna + Ground & Matching Transformer

just keeping it simple : simple is good ~ RHF

On 12/19/2010 2:05 PM, RHF wrote:

...
First a 'portable' AM/FM Shortwave Radio
+plus+
Second a shorter 30~45 Foot Random Wire Antenna

Third = Nothing Extra Required
No Attenuators
No Antenna Tuners
No Pre-Selectors

-wrt- Radio + Antenna + Ground & Matching Transformer

just keeping it simple : simple is good ~ RHF
.
.

It is simply physics. A long antenna will ALWAYS receive better and
more signals than a small one, even an amplified small one!

If you are happy with a small antenna, fine. It is only necessary for
all to know how to get the best and/or more signals -- the choice is
theirs ...

Regards,
JS

On 12/19/2010 3:52 PM, John Smith wrote:

All but the most blatant newbies should be able to deal with a "too good
an antenna."

Because of disinformation and "wives tales", I suspect there are many
with a tiny 30 ft. antenna who think they are realized "good reception"
and feeling quite capable of advising others.

It is simply time to fix this ...

Regards,
JS

You STILL don't get it. It is NOT an issue of "too good an antenna"; it
IS about too poor of a receiver front end.

Note: the OP's receiver in question is a fine receiver, BUT THE FRONT
END IS *NOT* DESIGNED FOR A VERY LONG ANTENNA.

On 12/19/2010 9:42 AM, dave wrote:

...
The antenna on a good portable is an active. It must be shorter than 1/4
wave at the highest frequency of interest to work at its optimum.

The EXT jack on a 7600 should be able to handle a proper wire antenna
10m or so.

On 12/19/2010 2:42 PM, John Smith wrote:

Physics is certain on this point. An antenna with a larger capture area
will always capture a stronger signal ... arguing that is pointless.

Regards,
JS

But nobody is arguing that.

NOT "pointless"; rather it is exactly the point.

Field strength is measured in volts per meter or micro volts per meter
(of antenna length).

Nobody is denying the point that you are locked in on, namely that a
longer antenna will give a stronger signal. This is indeed true...but it
is also THE PROBLEM (with the receiver specified by the OP).

The stronger signal from the longer antenna will overload the front end
of the receiver in question. THAT is the problem. And no, a down stream
(IF filter) is not the answer. Due to the front end overload, the signal
reaching the IF filter will -already- be damaged.

To anticipate your next response -- use of an attenuator -- will indeed
alleviate the problem. But just think for a minute: What is the point of
building a longer antenna to get a stronger signal that you are just
going to attenuate anyway.

Best regards and happy holidays,
Joe

Joe from Kokomo wrote:
On 12/19/2010 2:51 AM, John Smith wrote:

I'll just bet you, people with a 30' ft antenna are often wondering why
they don't hear what people with 100+ ft antenna hear ... don't ya'
think? ROFLOL

Regards,
JS

...and I'll just bet -you- [JS] that you are not familiar with the
concept of "front end overload". More [antenna] is NOT always better.

On 12/19/2010 3:14 PM, Bob Dobbs wrote:

"More antenna" can be accommodated
with pre-selectors and attenuators,
whereas less antenna can only generate wishes.

OK Bob...please explain why I would want to go to the trouble of
building a longer antenna to get a stronger signal...and then attenuate
that signal before it gets to the receiver. Seems it would be easier and
cheaper to build a shorter (proper antenna for the rcvr in question) in
the first place.

On 12/19/2010 5:08 PM, Joe from Kokomo wrote:

...
You STILL don't get it. It is NOT an issue of "too good an antenna"; it
IS about too poor of a receiver front end.

Note: the OP's receiver in question is a fine receiver, BUT THE FRONT
END IS *NOT* DESIGNED FOR A VERY LONG ANTENNA.

All I get is that you missed the importance of attenuators (heck, a
couple of variable resistors will do.)

Indeed, most decent radios already have an RF Gain control on them ...
this will be quite helpful.

Why you are making a non-problem into a problem and arguing for small
antennas is simply perplexing! To say the least!

And, for MW, a 300+ ft antenna is really needed for good DX ...

Regards,
JS

On 12/19/2010 5:09 PM, Joe from Kokomo wrote:

...
OK Bob...please explain why I would want to go to the trouble of
building a longer antenna to get a stronger signal...and then attenuate
that signal before it gets to the receiver. Seems it would be easier and
cheaper to build a shorter (proper antenna for the rcvr in question) in
the first place.

Well, I can help with that. Others, apparently NOT you, will want to
receive signals with the shorter antenna is just incapable of, for
starters ...

Regards,
JS