Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

donate to eham
   Home   Help Search  
Pages: Prev 1 ... 5 6 7 8 9 [10]
 on: Today at 10:03:24 AM 
Started by KI6VOS - Last post by KA4DPO
In 1974 I bought my KWM-2 and 516 f2 power supply and speaker from them.  I lived in Florida at the time and they took special care in packing it so it would make it across the country unharmed, it arrived in perfect condition.  My next major purchase from them was in 1977,  a Drake TR4CW with an AC4 and speaker, it was also well packed and in perfect condition (got that one from the Anaheim store).  I have since bought four or five other radios from them including my 599D Kenwood twins, wish I still had them.  My last major purchase from HRO was an IC-746Pro, the encoder failed almost immediately, I called Bob and they exchanged it no questions asked, I didn't have to pay a cent.

So All I can say is that in 40 years of doing business with them I have never had anything but good service from them.  To be honest, I have never had a bad experience with any of the amateur companies I have dealt with including DX Engineering, Universal Radio, AES, Juns, Texas Tower, Henry Radio, Associated, and Burghart, just to name a few.  I realize that things happen but I not found a company that did not want to please the customer.  I have had a couple of missteps with different vendors over the years and I found all of them were fair and reasonable in resolving any issues.  People who have problems with vendors usually are not willing to work with them and give them a reasonable opportunity to correct the situation.

 on: Today at 10:02:28 AM 
Started by K6RQR - Last post by K0BT
Thanks for the great suggestion!  I dreaded adding more rods after using a fence post driver to hammer through the caliche and river rocks.

 on: Today at 09:57:34 AM 
Started by KD8M - Last post by LA9XNA
Don't trust anything but the official Mars mod / extended range mod from Icom.
For a radio model  like the IC-7000 there might be several "generations" before end of production. The differences might be substantial from generation to generation. This rig where in production for a long time.
An example is the IC-910H this one has had at least 3 different fornt panel PCB over the time of production.
I have a official icom "mars" mod pdf  from Icom just not right here, but have found you the llink for the same online.

 on: Today at 09:55:30 AM 
Started by W9YNFSON - Last post by K3STX
He is trying to sell the radios for as much money as possible! He LIKES inflated prices.

EBay completed listings will give you an idea of the ballpark; whether $100 or $1000.


 on: Today at 09:53:41 AM 
Started by KD2E - Last post by KAPT4560
 The R8A may be able to drive a quality 3-way home stereo speaker for comparison. Are you trying to listen to music or voice? Are you trying to get better hi or low frequency response? Where do you typically keep your tone control set at?
The 4Ω speaker impedance value should match to output impedance. The amp spec says 2.5 watts @ 10% distortion and while that isn't 'hi-fi', it should be OK.

 on: Today at 09:34:05 AM 
Started by W2IRT - Last post by N5UD
Bureau cards...I guess over the years I have had 50% return success on my outgoing, if even that high.

I mainly use ARRL outgoing for QSL's received via the bureau. Guys with working bureau's that want my card. Quite often for JA or DL I send direct to their bureau. Don't bother with ARRL.

Now....just where does the current $49 per year of dues go ? Should not some of the annual dues go to support IN/OUT bureau ? Seems like it always did years ago. Part of the "ham radio spirit". For HOBBY club dues....$49 seems a bit high.

It looks sad that possibly BEAN COUNTERS may have taken charge as in much of the corporate America trying to make every function pay for itself.

The other national clubs don't seem to have this bureau problem.

Well my two cents, BEAN COUNTERS !

73 Tony N5UD

 on: Today at 09:24:35 AM 
Started by WD4ELG - Last post by K6BRN
To accurately measure RF power you will need as direct a connection between the driver (radio) and a well matched dummy load as possible, using good quality coax with connectors in good shape.  The Wavenode HF-1 sensor will need to be inserted between the driver and dummy load using two short lengths of coax.  And once that is done, the Wavenode reading may still be off by 5-10%, generally on the conservative (low) side.

For an interesting and informative experiment, rerun your power measurement any way you like and record and compare the peak and average readings from the Wavenode box and from the Wavenode software running on a PC.  The box vs. PC readings will not be the same.  Why?  Allen at Wavenode has explained that the box uses fixed point math whereas the PC software uses more accurate floating point math, so the two often disagree on SWR and power to a small degree.

Moral:  To get power readings that are as accurate as possible, simplify connections as much as possible, use good, very short cables and connectors and a well matched dummy load.  And even then, do not expect accuracy better than 5-10% unless you are using calibrated professional grade equipment, and don't worry too much about dicrepancies that fall in this range - they may not be real and certainly make very little difference.  RF performance is logarithmic, for the most part.  2x (3db) and 10 x (10 db) differences are significant.  5-10%, not so much.

 I have and use two WN-2 units, one WN-2d and nine sensors - very familiar with this equipment.  It is very handy, reasonably accurate, works well and is cost effective.  But it is not lab grade (nor is other ham radio dedicated equipment on the market, despite claims, IMHO).

Brian - K6BRN

 on: Today at 09:16:50 AM 
Started by KD2BOB - Last post by K2GWK
Read Glen's post above. He understands  what affects efficiency. It is more about the ground system which is why I don't believe your antenna works without radials.

Why don't you read it. It does not talk above a non resonant antenna on 80m.  It must really bug the S$!T out of you that my vertical actually works pretty good on 80 and 40 without radials. Bet you never tried one mounted on a 7 foot field fence pole driven 6 feet in ground either....

I don't know why I even try debating with you. It's like talking to the wall. I could care less about your vertical as I have a beam antenna and a dipole for 40 meters. I just do not believe your vertical works as well as you claim. With good athmospheric conditions even a watt will get you around the world.

The real disadvantage of a non resonant vertical is the loss due to vswr making a tuner at the antenna a necessity. It has nothing to do with efficiency. The manufacturers claim that the feedline needs to be a 100' minimum is bullshit also. If a tuner at the antenna is not possible the antenna would do better with ladder line.

 on: Today at 08:58:49 AM 
Started by KC2TRX - Last post by K6BRN
I've been experimenting with and have disassembled an enclosed lower power end-fed antenna matching network for 10-80M.  It contains two toriodal cores wound as a matching transformer and two ceramic capacitors.  What I've found is that the toroidal cores, enclosed in an air-tight box and suspended in the center of the box by thin connecting wires have a very, very poor heat dissipation path.  And this is a very common mechanical/thermal design for EF matching networks.

As a result, when cold, the matching transformer will handle quite a bit of power.  But as it warms up over time, even from modest but continuous power application on RTTY (or even JT-65/JT-9), it will then refuse to tolerate a sudden power increase gracefully and the SWR will rise, slowly at first, then skyrocket as the core(s) Curie temperature is exceeded.  Even when this happens, the outside of the matching transformer box is just moderately warm - the thermal path is that poor.

This happens when (for example) running RTTY at 50W on and off for an hour, then turning up the power to about 200W to close the link on a marginal contact.  Within a minute, SWR will begin to rise, then jump to 10+.  After that, its a long cooling off period, or back to JT-65 at no more than 20W.

The higher power matching networks for the same application I've tried work much better and appear to have cores with higher Curie temperatures, thermal mass and efficiency.

Moral of the story:  Install the highest power matching network you can - they are not that more expensive or notably larger outside (6 vs. 54 inches).

I'd love to develop a way of cooling the matching tranformer cores, too, either with oil or air, without causing other practical problems.  Has anyone done this?

Brian - K6BRN

 on: Today at 08:55:39 AM 
Started by VE3VEE - Last post by N5VYS
FJ/N2IEN 160M a new one on that band...via LoTW. Thanks.

Obie N5VYS

Pages: Prev 1 ... 5 6 7 8 9 [10]
Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!