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Coast to coast on my ubitx yesterday

_Dave_ K0MBT
 

I wasn't really trying but this is still only the 4th day that I have had my ubitx.
Using phone I was able to work stations from coast to coast of the united states. I did it on the 80 meter band. and used a homemade trap 80/40 dipole. My radio could put about 25 watts pp. My power source is a 10 amp linear 13.8v Tripp-Lite. 
 
Logged stations in Maryland, Florida, NY,Montana, Utah, California and states in between. Most gave me signal reports of 5/4 to 5/9 I got a couple of 4s and a 3/3 I got a 2/1 when working a Missouri station, I am in Missouri. The longest contact was 1500 miles in Northern California.

I am using the stock electret microphone.

Have also done some CQ ing on 7277. I did find two Hams with bitx radios One that had his radio out of the box but had not put it together. The other was N3GO Gary in Raleigh NC, He had a bitx40 that was modified. I talked to him on both my ubitx and my bitx40. He said that there was not much difference in signal. I definitely hear better on the ubitx.  

Dave 
K0MBT

Tim Gorman
 

You were getting 25 watts Peak-to-Peak? Or you were getting 25 volts
peak-to-peak?

tim ab0wr

On Fri, 20 Apr 2018 05:00:23 -0700
davesters@... wrote:

I wasn't really trying but this is still only the 4th day that I have
had my ubitx. Using phone I was able to work stations from coast to
coast of the united states. I did it on the 80 meter band. and used a
homemade trap 80/40 dipole. My radio could put about 25 watts pp. My
power source is a 10 amp linear 13.8v Tripp-Lite. Logged stations in
Maryland, Florida, NY,Montana, Utah, California and states in
between. Most gave me signal reports of 5/4 to 5/9 I got a couple of
4s and a 3/3 I got a 2/1 when working a Missouri station, I am in
Missouri. The longest contact was 1500 miles in Northern California.

I am using the stock electret microphone.

Have also done some CQ ing on 7277. I did find two Hams with bitx
radios One that had his radio out of the box but had not put it
together. The other was N3GO Gary in Raleigh NC, He had a bitx40 that
was modified. I talked to him on both my ubitx and my bitx40. He said
that there was not much difference in signal. I definitely hear
better on the ubitx.  

Dave 
K0MBT

_Dave_ K0MBT
 

Hi Tim
I was getting 25 watts on my watt meter. om 80m.

Today hooked up a 10m dipole and got 2.5watts with keyer down. With a low swr. 
Delta Alpha Victor Echo

Tim Gorman
 

Do you have access to an oscilloscope or spectrum analyzer?

The most I can get out of mine was about 15 watts. And when I go over
10 watts the two-tone, 3rd order IMD rises to only about 18db, a
terrible figure. I had to decrease my output to 10 watts to have a
reasonable 3rd order IMD.

What are you running for voltage on the power amplifier?

tim ab0wr

On Sat, 21 Apr 2018 03:48:03 -0700
davesters@... wrote:

Hi Tim
I was getting 25 watts on my watt meter. om 80m.

Today hooked up a 10m dipole and got 2.5watts with keyer down. With a
low swr. Delta Alpha Victor Echo

_Dave_ K0MBT
 

Hi Tim
Yeah I do have a an oscope but the readings I gave you were from my swr meter. Is my meter right?? It is a cheap cb meter. Still the readings seem to close to what others have posted. Probably is my location and atmospherics but was able to reach out and touch someone as the old Bell ads once said. Yesterday I contacted someone in Tucson and today it was Nantucket. 

My antenna is a homemade choked dipole resonant on 40 and 80. Hung between trees overlooking a ravine. I use recycled RG6 from an old residential television system. I have thought about upgrading it but then I wonder what would be gained. 

I am running 13.8 on all circuits. I put details in my first post. 

I did not check the bias on the pa. But did go through the other calibration steps. The bfo was not set very close. 

This is my main HF rig now and probably will be for some time. I have thought about making the bitx40 a mobile unit. 

Tim Gorman
 

Dave,

I would trust your meter more to tell you the swr than the actual
power.

If you have a dummy load you can hook up then this site:
http://www.ab4oj.com/test/pwrmeas.html
will give you good info on how to accurately measure your power using
your oscilloscope.

tim ab0wr


On Sat, 21 Apr 2018 10:50:28 -0700
davesters@... wrote:

Hi Tim
Yeah I do have a an oscope but the readings I gave you were from my
swr meter. Is my meter right?? It is a cheap cb meter. Still the
readings seem to close to what others have posted. Probably is my
location and atmospherics but was able to reach out and touch someone
as the old Bell ads once said. Yesterday I contacted someone in
Tucson and today it was Nantucket. 

My antenna is a homemade choked dipole resonant on 40 and 80. Hung
between trees overlooking a ravine. I use recycled RG6 from an old
residential television system. I have thought about upgrading it but
then I wonder what would be gained. 

I am running 13.8 on all circuits. I put details in my first post. 

I did not check the bias on the pa. But did go through the other
calibration steps. The bfo was not set very close. 

This is my main HF rig now and probably will be for some time. I have
thought about making the bitx40 a mobile unit.

Tim Gorman
 

Dave,

This is also a good site for how to measure output power.

http://dudleylab.com/Appnote-4-Power-tests1.pdf

tim ab0wr


On Sat, 21 Apr 2018 10:50:28 -0700
davesters@... wrote:

Hi Tim
Yeah I do have a an oscope but the readings I gave you were from my
swr meter. Is my meter right?? It is a cheap cb meter. Still the
readings seem to close to what others have posted. Probably is my
location and atmospherics but was able to reach out and touch someone
as the old Bell ads once said. Yesterday I contacted someone in
Tucson and today it was Nantucket. 

My antenna is a homemade choked dipole resonant on 40 and 80. Hung
between trees overlooking a ravine. I use recycled RG6 from an old
residential television system. I have thought about upgrading it but
then I wonder what would be gained. 

I am running 13.8 on all circuits. I put details in my first post. 

I did not check the bias on the pa. But did go through the other
calibration steps. The bfo was not set very close. 

This is my main HF rig now and probably will be for some time. I have
thought about making the bitx40 a mobile unit.

_Dave_ K0MBT
 

Hi Tim
I appreciate the links that you have directed at me.
Dave
k0mbt