El 06-07-11 1:03, rkhalona escribió:
On Jul 1, 8:33 pm, wrote:
On Jul 1, 6:36 pm, wrote:





On Jul 1, 2:55 am, wrote:

On Jun 29, 11:12 am, wrote:

On Jun 26, 8:20 am, wrote:

On Jun 23, 10:31 am, wrote:

Any owners of this new radio here?
I am wondering if you are hearing any (audible) difference when you
switch between the wide and narrow bandwidth settings in AM mode.

Thanks for your answers.

Ramon Khalona

"RK",

Go Here for the Sangean Company webpage
for the Sangean ATS-909XAM/FM/SW Receiverhttp://www.sangean.com/products/products_main.asp?pid=71&pan=9&um=3
-has-down-loads-for-

* Manual PDF
-note- Read Page 32
"Switch Setting" : AM Narrrow / Wide
-says- The Filter Switch works NW in the AM Mode
-and- Is Always Narrow in SSB Mode

* Specification PDF

* Flyer PDF

Call/Contact Sangean USA and ask then the
Question as to the Band-Widths of the AM
Mode Wide and Narrow Filters in the Sangean
ATS-909XAM/FM/SW Receiverhttp://www.sangean.com/contact_us/contact_us.asp?um=5
INFO : Phone + eMail
+ On-Line 'Web-Request' Form
.
.
-alternative-
Radio Labs Support may be able to answer
the Question as to the Band-Widths of the AM
Mode Wide and Narrow Filters in the Sangean
ATS-909XAM/FM/SW Receiverhttp://www.radiolabs.com/support/
.
.

Thanks RHF. I am looking for other users' experience. My unit comes
from Radio Labs, with the filter upgrade (their so-called, "Clearmod"
modification).
The difference when I switch from AM wide to narrow is almost always
inaudible and, for all practical purposes, does not make any
difference without detuning the radio
in slow mode. I wonder if owners of the stock radio experience the
same.
(The Radio Labs people think this is the way the radio is supposed to
work, which I found puzzling and surprising)

RK

RK,

If you have a Very W-I-D-E 'Wide' IF Filter +8 kHz
and a not-so-wide 'Wide' IF Filter ~4 kHz you may
NOT hear or detect too much difference between the
two when it comes to AM-Mode Radio Reception.

However, If you have a Standard 'Wide' IF Filter
~5 kHz and a Narrow IF Filter -3 kHz you may well
Hear a/r Detect some real difference between the
two when it comes to AM-Mode Radio Reception.

What "kHz" and "Shape Factor" Rad-Labs 'claim'
for their Wide and Narrow IF Filter in the
Mod'ed Sangean ATS-909XRadio ?

Sangean ATS909X- Modified for Clarityhttp://www.radiolabs.com/products/receivers/ats-909x-mod.php

iwtk ~ RHF
.
.- Hide quoted text -

- Show quoted text -

Hi RHF,

Radio Labs claims they have used 4.5 KHz for wide and 2 KHz for
narrow. As I said in my response to Dave, one should be able to hear
the difference between these pretty easily (for reference, my Drake
SW8 has 6, 4 and 2.4 KHz bandwidths, and one can hear the difference
between all three pretty well, especially in going from the middle to
the lowest bandwidth because the narrowest filter muffles the audio
distinctly). I just wanted to hear about other users' experience,
wether they have the stock or modified radio.
Thanks for your reply.

RK- Hide quoted text -

- Show quoted text -

You can try this simple test I just thought of . A) Tune to a
loud,stable AM-modulated station . B) Turn the SSB on . C) Play with
USB/LSB setting . D) Detune the received frequency slightly ( no more
than 1-2 KHz) ,so you hear the beat sound increasing or decrease in
the pitch . E) Play with the wide/narrow setting . F) If the filters
are really there- -the change must be very obvious .- Hide quoted text -

- Show quoted text -

Hi there again,

The reason this test does not work with this radio is that in SSB
mode, the radio is automatically set to the narrow bandwidth and the
switch becomes
inoperable, hence there is no difference. However, when you tune to a
strong station in AM mode on narrow and then detune by several KHz so
that the station is inaudible and you switch to wide, the station is
audible again. This suggests the switch is working, but the
bandwidths used are not that different to make for an audible
difference. Several users of the stock radio have reported similar
behavior (i.e., not much difference between wide and narrow
bandwidths).
Thanks again for your suggestion.

RK

Hello Ramon,

Really strange, as with the "old" 909, the difference is clearly
noticable, even with the tone setting on news.

They Sangean guys probalby did something weird, as normally you work
on "wide" only in case of interference from an adjacent station or
noise you switch to the narrow setting to get a readable signal, but
with reduced audio quality.

I checked it on several stations. Now (00:00h UTC), Radio Havana
reaches Netherlands on an indoor antenna (6000 kHz). Did you test it
also on a weak (noisy) station?

Maybe you can contact a radio amateur to do some measurements on the
radio to find out what is the root cause for the behavior.

With kind regards,


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