Trade Modded DX-398 For Scanner
 

Here is a RS DX-398 in great condition. This radio has several improvements
that have been implimented over a "stock radio". These are as follows: 1-an
additional broadband rf amplifier has been added internally to boost
reception with the telescopic antenna. This really helps boost weak signals.
2-Tuning mute and smooth knob tuning to eliminate the stepped tuning knob
action and chugging when bandscanning with tuning knob. This makes for much
better feel when tuning than on a stock radio. 3-The audio has been improved
to get rid of the tinny sound normally found in a stock radio. It has good
volume and punch. This one is easy to listen to for extended time. 4-The
stock radio has a very weak green led backlight system for the LCD display.
It makes it hard to read in dim light. The dim green leds have been change
to brighter blue leds. This makes it much easier to see in dim light. Also
note that when using an AC adaptor the light can be selected to stay on all
the time. 5-The stock radio has a very slow AGC, this has been corrected to
a fast AGC time which makes station reception on worldband much better.
These modifications make an already good radio much better. This is the best
portable I have owned. The audio is much better than stock. Sensitivity is
excellent! I can listen to 80 meter hams easily with the whip antenna! I
just don't use it much. I need a scanner. Thanks for reading!

I'm looking to trade for a mint RS Pro-95 or ?

DeWayne K9KZ

DeWayne ...

^ ... Morse Code (obsolete) ...

Morse code isn't obsolete -- it can still extend to greater distances than
voice.

Another advantage of Morse code is that several conversations can
simultaneously exist on a single frequency. Each station uses a tone
different enough to be distinguished by ear and an experienced operator can
mentally filter out all but the tone he's copying.

Frank

"Frank" wrote in message
news:01c386e0$9a92e3e0$0125250a@yludnifduhzssbbv.. .
... [SNIP]
Another advantage of Morse code is that several conversations can
simultaneously exist on a single frequency. Each station uses a tone
different enough to be distinguished by ear and an experienced operator
can
mentally filter out all but the tone he's copying.

This is not true.

If the "tone" is different at all, then the carrier is on a different
frequency.

Two (or more) CW transmissions on the same frequency will have the identical
"tone".

You can fit CW transmissions very close together, but not on the same
"single frequency".

Budgie wrote:
This is not true.

If the "tone" is different at all, then the carrier is on a different
frequency.

Two (or more) CW transmissions on the same frequency will have the identical
"tone".

You can fit CW transmissions very close together, but not on the same
"single frequency".


If it's code, it's not on a single frequency in the first place. Not only
theorically! Listen to code through a 10Hz filter and it's nearly uncopyiable.

The audio effect is that the filter rings as loudly as the signal. But it's
actually a mathematical effect. You're cutting out too much of the bandwidth
that the code actually occupies.
--
Ron Hardin


On the internet, nobody knows you're a jerk.

^ Budgie wrote:
^ If the "tone" is different at all, then the carrier is on
^ a different frequency.

OK, I was under the impression that a tone was transmitter on the carrier and
that the tone could be adjusted. But that would be modulation.


Ron Hardin ...
^ If it's code, it's not on a single frequency in the first place.

A single freq is not possible. You're only picking on words. "A single
frequency" always implies the frequency that the signal is centered on.

Another advantage is that CW has a narrower bandwidth than any voice
modulated signal.

Frank

Spurious Noise yI5eb.34774$Ms2.224@fed1read03...

^ Just FYI:
^ CW Bandwidth = wpm X 4 (e.g., 40 WPM = 160 Hz)
^ From the ARRL License Manual 1976:
^ "With proper shaping, the necessary keying bandwidth is equal to 4
^ times the speed in words per minute for International Morse Code;
^ e.g. at 25 words per minute, the bandwidth is approximately 100
^ cycles."

Thank you. SSB is about twice that right? And isn't SSB the narrowest voice
emission?

Frank

Jack ...

^ CW is an unmodulated transmission ...

^ Radioteletype (RTTY and AFSK) also use unmodulated carriers. On HF
^ bands, most use unmodulated Lower Sideband. As with CW, the receiver
^ reinserts the carrier, causing the AF-shifted beat note.

And CW requires only the transceiver and key while the other data types
require another, often more expensive, piece of hardware.


So am I still correct that the advantages of CW a

- Narrower bandwidth. The bandwidth is effectively even narrower because
overlapping adjacent signals can still be distinguished by the human ear.

- Greater effective range.

- Less equipment than other data types, which also have greater bandwidth.

- Can be used without a microphone and without a key. Just open the box and
short a couple of contacts.

Frank

"Frank" schreef in bericht
news:01c3873c$96939df0$0125250a@preimuffyaouanyy.. .
Spurious Noise yI5eb.34774$Ms2.224@fed1read03...

^ Just FYI:
^ CW Bandwidth = wpm X 4 (e.g., 40 WPM = 160 Hz)
^ From the ARRL License Manual 1976:
^ "With proper shaping, the necessary keying bandwidth is equal to 4
^ times the speed in words per minute for International Morse Code;
^ e.g. at 25 words per minute, the bandwidth is approximately 100
^ cycles."

Thank you. SSB is about twice that right? And isn't SSB the narrowest
voice
emission?

No, SSB is about 20 times the bandwith of CW

MRe PE1NQR

Frank wrote:
DeWayne ...

^ ... Morse Code (obsolete) ...

Morse code isn't obsolete -- it can still extend to greater distances than
voice.

Another advantage of Morse code is that several conversations can
simultaneously exist on a single frequency. Each station uses a tone
different enough to be distinguished by ear and an experienced operator can
mentally filter out all but the tone he's copying.

Frank


With BPL coming Morse Code might be the only way left to communicate on HF.

Sorry I'm not a ham and I don't want to see CW go. It call BASICS!
Once you start forgetting about the basics then you start developing a
backwards nation.

Just look at school, they don't teach the basics any more they just
throw the kids on computers. Do you know a single McDonalds employee
who can make change in their head???

CW isn't hard to learn, not even a ham and I can receive 15 WPM and
actually enjoy it....

George
http://www.MilAirComms.com

Normally the bandwidth of an SSB transmission is about 3.5 kHz. It of course
can be much wider if the transmitter passes frequencies above that. Listen
around 3.945 MHz and you will hear a group that has enhanced audio and they
get broadcast quality SSB along with the expected increase in bandwidth
..
"Frank" wrote in message
news:01c3873c$96939df0$0125250a@preimuffyaouanyy.. .
Spurious Noise yI5eb.34774$Ms2.224@fed1read03...

^ Just FYI:
^ CW Bandwidth = wpm X 4 (e.g., 40 WPM = 160 Hz)
^ From the ARRL License Manual 1976:
^ "With proper shaping, the necessary keying bandwidth is equal to 4
^ times the speed in words per minute for International Morse Code;
^ e.g. at 25 words per minute, the bandwidth is approximately 100
^ cycles."

Thank you. SSB is about twice that right? And isn't SSB the narrowest
voice
emission?

Frank