On Jun 4, 4:11*pm, Gregg wrote:
On Jun 4, 6:38*am, RHF wrote:



On Jun 3, 2:35*pm, Wimpie wrote:

On 3 jun, 22:22, "bw" wrote:

"George Orwell" wrote in message

t...

I understand that attaching an external antenna will disable the build in
AM ferrite antenna.
My question, is this is a good thing? Will I pick up more with a 100 foot
longware versus a standard ferrite antenna?

The whip is disabled, not the ferrite.

Hello,

From memory I also thought that the external antenna is for short wave
only (so not for the AM broadcast band). The manual, however, says
that is does work on "MW" also (page 35GB). I don't have the receiver
over here so I cannot verify it.

- The manual also says it outputs DC,

The DC Voltage is a 'sense' switching voltage
for the external Sony active Antenna.
1 - Turn the Radio "On" and the Voltage tells the
Active Antenna to turn "On".
3 - Turn the Radio "Off" and [No] Voltage tells the
Active Antenna to turn "Off".

- so you need to avoid a short between the
- ext. antenna input and ground of the receiver.

This is not a problem since Sony built-in Circuit
Protection because this is afterall the same
plug used for the External Antenna Input
Tip = Antenna [DC 'Sense' Voltage]
Barrel = Ground

- Unless you are in a very remote area, 100ft wire at reasonable
height
- above ground will overload the receiver very likely. *You can better
- use a shorter wire far from interference sources

The general Shortwave Listener (SWL) External
Wire Antenna recommendation for most SWL
'portable' Radios is a Length of around 30~35 Feet.

- and use coaxial cable between the antenna wire
- and your receiver.

Coax Cable can help in RFI Noise reduction {pick-up)
coming from the Antenna into the Radio.
More Signal & Less Noise = Better Listening

- You need to connect your wire to a large metallic structure or
ground
- away from interference sources, otherwise the cable will guide
indoor
- interference to your antenna.

Some SWL 'portable' Radios that are powered with
Batteries only and not connected to the AC Mains
will work better {more signal and less noise} with
just the External Antenna 'connection' only and NO
Ground connection. *While others seam to work
better {more signal and less noise} with both the
External Antenna and Ground 'connections'.
-hint- try both

-IF- You are using AC Mains for Power or AC via
a Wall Transformer : Then a good Earthen Ground
'connection' is recommended for Safety.

Best regards,

Wim
PA3DJS
www.tetech.nl
remove abc first in case of PM

~ RHF
*.- Hide quoted text -

- Show quoted text -

- Good post RHF. The big gripe many have on these portables is the old
- "it eats through batteries."
- The difference between the 7600 and the 398/909 isn't that big of a
- difference in battery drain. Now I know "someone" will say different
- in here as I expect but the way I always looked at owning a portable
- is that you should use batteries to begin with.
-
- You can have the quietest environment. You can have the best
grounded
- antenna etc. etc. But in respect to any portable, if you run it off
- batteries it's going to be quieter, period. If you listen so much to
- your portable that battery drain is a concern, you have two
remedies.
-
- Headphones. If you use cans your batteries will last a good long
time.
- And number two, which I do. Have two sets (I have five) of
- rechargeable batteries and a good charger. Problem solved. If you
are
- buying a portable and you are so worried about battery consumption -
- then IMO - you should get a desktop. :-)

The Sony ICF-SW7600GR runs on 6 VDC, so a single
6 VDC 7 AH rated Battery with a Charger will power
an AC Mains 'free' portable SW Radio for a coupe of
weeks to a month of Daily {All Night} Radio Listening.
http://www.atbatt.com/sealed-lead-ac...c/m/6v-7ah.asp
* Works great as a Camping & Field-Day Power
Source that will reliably last the whole weekend
and run 48 Hours of portable SW Radio Listening
on one charge.
** Add a LED Utility Light {6 VDC} along with
a Table and Chair and just listen . . .
http://www.amazon.com/gp/product/B002UN4F7Y

FWIW many 'portable' AM FM Shortwave Radios run
on 6 VDC and have a Jack for an External 6 VDC Power
Input for use with an AC-to-DC Wall Transformer.
Instead use a large longer lasting external 6 VDC
Rechargeable Battery and reduce some of your
potential AC Mains power source RFI/Noise from
a AC-to-DC Wall Transformer.

hth ~ RHF