Low Power Output? 6300 or 6500

W5XZ - dan

I need to look up one of the local guys who has an LP-100.  I THINK that thing has traceable NIST
accuracy...if calibrated from the factory...before i can say with some confidence of accuracy that
my Pout is low...don't have one in my shack...yet...  

OTOH, i'm checking with a buddy for a simple, but reasonably accurate way to measure r.f. voltage around the 100 watt level...looks like 70.7 volts = 100w, to me..

DrTeeth

Steve,

Are you saying that the input voltage reading from DDUtil is not reliable? AIUI, and am happy to be proven wrong, it gets its info from my 6300 itself. Plus, I do not see any significant increase in power by changing my key-down voltage from its dropped value to 14.0v.

73.

Steve K9ZW

Hi Guy

I cannot say, as the versions of the software was pre-release program software, I don't think I even had DDUTIL at the time, and the power supply swap was intuitively in keeping with reduced output from other radios I had experienced. 

Was annoying as I had to change the power supply end of the beautifully done power cable to suit the larger supply.

The only generalization I should make is "It is worth trying another, preferably larger power supply and checking all aspects of your power-supply into the radio cabling before sending your radio in for a checkup."  Of course YMMV.

73

Steve

K9ZW

AA0KM

Steve K9ZW

Is there a similar guide for connector contact surface area & connector conductor sizes? 

I've long wondered if the massive reduction from a nice cable to a small ring or a single clamp/crimp plays a role?

73

Steve

K9ZW

Joe, KQ1Q

My 6300 puts out from 97-100 watts into a dummy load as measured by a LP-100A. That's on 80, 40, 20 and 10m. Tested using 9-inch long 12 gauge cables from a switching 30 amp supply. Voltage under load as measured by Fluke DVM was 13.8 volts.

As already mentioned, RF power output is very sensitive to DC supply voltage at the input terminals. If voltage sags to only about 12.8 volts, RF power out diminishes several watts, in some cases down to the high 80s. The spec in the ver. 1.4.0 Flex 6000 hardware Reference Manual states 100 watts CW out *at* 13.8 volts DC supply. If you don't measure 13.8 volts at the radio DC input terminals under load, it's not getting the specified voltage for full power RF output.

Ken - NM9P

I don't know, But I would love to convert my old backup Pyramid power supply from posts to Power Pole connectors, if not only for convenience!

DrTeeth

You sound like a broken record, 'click,' you sound like a broken record, 'click' etc ad infinitum.

Ed, K0KC

"Record" ??? I think I remember those things!

Paul Christensen, W9AC

I ran into this issue a few months ago and it turned out to be slight loss through a PL-259 connector. 

I run my supply at +14.5V using the Flex-supplied cable with Powepoles.  This results in better than +14V at the Flex 6700.  The power connection is fastened right on to the supply's 1/4-inch bolts.  If a RigRunner or similar DC manifold is used to distribute +12V power through the shack, I strongly encourage folks to connect their transceivers direct to the power supply and not through the RigRunner. 

Cascading Anderson Powerpoles can result in losses that quickly add up.  When we're asking near 20A of current through them, even very small resistance affects voltage at the transceiver.  I won't get into a philosophical diatribe about Powerpoles, but I do wish transceiver manufacturers would parallel these with a real power connector, like a pair of 1/4-inch bolts. 

Next, when these power issues come up, it's important to measure power right at the output of the transceiver into a known 50-ohm load.  When a wattmeter is inserted after filters and complex switch arrangements, one can easily see the accumulated loss through the coaxial distribution.  That's what was happening here.  I was seeing 85W after the switches and filters, but >95W at the output of the Flex 6700. 

Any time a wattmeter's calibration is suspect, an easy way to verify the result is to measure RF voltage with a sufficiently-high-bandwidth oscilloscope at the 50-ohm load.  Going one step further toward calibration, one can calibrate the scope against a known AC voltage.     

Paul, W9AC

DrTeeth

Ed, a few years ago my daughter asked me, "Daddy, in the old days when everything was in black and white...". She had seen some old films and came to the only logical conclusion a cute youngster could. She's now grown up and a teenager, :-(, hi hi.

Steve N4LQ

Ok. I chopped my DC power lead down to 16" and soldered a pair of heavy duty lugs on the end. The PSU is an Astron 35m, fairly new. I adjusted its voltage for 14.0 as measured at the terminals. Then, with the DVM probes jammed into the Anderson PP on the 6500 I measured exactly 13.96v, key down. Not bad! 
Power output now at 95 watts max, any band. I also used a different, shorter coax jumper to the meter and dummy load. 
I hated to shorten my cord. Now I need to order another one in case I want to relocate the rig. 
So by increasing my voltage and shortening the cord I gained about 3 watts maybe. It's still low in my book. 
BTW: Both my external watt-meter and the one in SmartSDR read nearly the same.....>Low

As for those Anderson Ppoles, I think they are dinky. The tiny **** of metal inside them seems inadequate ....What is the part number for those so I can order more? 

KY6LA_Howard

So you have proven it's the power supply/cord/connector issue..  Not the radio

If you are still determined to get exactly 100W you can raise your supply voltage to 14.2V and that should get you 100W.

Steve N4LQ

Just the opposite. Any radio I've ever had has produced 100 watts or more with much longer and smaller gauge cable and less DC voltage. I have no urge to crank up the voltage any higher.
Being determined to get 100 watts is not a negative on my part either. 

So here's the "out" for Flex:

Transmitter Specifications

• RF Output Power:  1-100W nominal SSB, CW, FM, RTTY, Digital; 1-25W nominal AM

Websters: 
NOMINAL

Existing as something in name only : not actual or real

: very small in amount

Jim Gilliam

I have to admit you are right. Nominal is a very vague term and really has no place in an engineering spec. Good point.

JIm, k6QE

KY6LA_Howard

As an Engineer I take exception to that comment "no place in an engineering spec"  

Heck REAL WORLD electronic components have all sorts of variations is specification.   Just look at the simple example of a resistor.. 68 Ohms  Plus or Minus (1% , 2%, 5%)...

Or listen to the Lunar Landing.. "Conditions Nominal"  

Jim Gilliam

You made my point!!! Why doesn't Flex say the same thing 100 Watts, +- 10%. Nominal could be plus or minus 99%!

Steve N4LQ

Copied from factory web sites. 
No mention of "nominal"

Kenwood TS-590sg 
HF Output Power100 W SSB/FM/CW/FSK, 25 W AM
------------------------------------------------------------------------
Elecraft K3
Output Power: 200 mW –100 W, ALC controlled (Reduced power on AM.)
----------------------------------------------------------------------------------
ICOM IC-718

Output power 2 - 100W SSB, CW, RTTY

------------------------------------------------------------------

Yaesu FT-950

60 - 6 meters, 100 Watts of Reliable Power 

  

KY6LA_Howard

BTW.... Up to now I had never measured my 6700 Output Power as i usually run it at less than 20W or it will drive my 2K-FA well beyond legal limits...

So it was an interesting exercise to drag out several different digital wattmeters and compare the results...   I achieved Exactly 100W output with

an input voltage of 14.21 volts before the Fuse in the 6700 key up

and 13.68 volts before the Fuse in the 6700 key down

DDUTIL Readout was a constant 14.4Volts

SWR 1.06

Bottom Line .. I am losing 0.53V drop between my 50A Power Supply and 8 G cables...

BTW.. Powerpoles are definitely the standard connections for most EMCOMM Communications...   HRO sells powerpoles

k3Tim

Nominal....  I don't know...  NASA used that all the time in the Mercury  / Gemini / Apollio programs.  As in "O2 is nominal", trajectory "nominal"

I haven't found the formula but knowing power = V^2 / R where R is in ohms.  It would seem power is very dependent on voltage.

hold on, checked the ARRL Handbook (2014) and see an RF amp  with 250Watts OUTPUT using a pair of VRF151 MosFets in class AB @ 48 Volts.  The broadband match is 4:1.   So we have V = 48 volts and R=50/4 = 12.5 
V^2 / R =   48 x 48 / 12.5 = 184 Watts   * 2 devices = 368W *  0.70 percent efficient (class AB)  = 258 W

Joe, KQ1Q

There are three sizes of Power Pole connectors, for 15 amp, 30 amp and 45 amps, each requiring unique contacts and wire gauges. Scroll down this page to see the options: http://www.powerwerx.com/anderson-powerpoles/powerpole-sets/45-amp-permanently-bonded-red-black-ande...

I personally use 45 amp Power Poles and 10 gauge wires for the main DC supply to a 100 watt radio, but I guess technically 30 amp Power Poles and 12-14 ga. might work if very short.

Re Flex 6000 RF output power, ideally everyone testing should use the same procedure, whatever that is. E.g, do you test the initial power, or after 30 sec, on every band, etc? Into a dummy load? How much degradation is expected after 30 sec or 60 sec?

Personally I'd suggest only testing into a 50 ohm dummy load, only with very short heavy gauge DC cables, and only after verifying the DC supply can maintain 13.8 volts at the radio input terminals. Further I'd suggest everybody standardize on some to-be-determined timing such as take the RF output measurement after 15 seconds or 30 seconds of key down, and test multiple bands not just one.

Since the final amp is a linear device and must dissipate significant heat, part of meeting the spec is how the PA handles temperature compensation under load. For that reason it seems appropriate to test after x number of seconds, maybe with some recovery time or duty cycle spec between repeated tests, but I don't know what fair numbers would be or what the common industry practice is for such testing.

Unfortunately the hardware reference manual just states 100 watts, with no +/- percentage or any other qualifying info except 13.8 volts DC.

Steve N4LQ

So what size is on the Flex 6000? 30 Amp?

Joe, KQ1Q

I haven't measured it but I think it ships with 45 amp Power Poles and 10 gauge cable. That's just what it feels like.

Ken - NM9P

So does west mountain engineering, and other suppliers that you will meet at hamfests. They are inexpensive and versatile. For the big rigs, get the 45 amp version rather than the 30 amp. They are compatible but accommodate a larger gauge of wire.

Joe, KQ1Q

BTW, Fluke has fine-tip test probes which can easily get inside a Power Pole connector: http://www.amazon.com/Fluke-TL910-Electronic-Test-Probes/dp/B000VRJH0G

Al_NN4ZZ

Another option is to make your own.....using a straight pin or snip off a section from a safety pin.   I have a set of alligator leads with pin tips in the drawer and they work fine for this.

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com

Joe, KQ1Q

I just re-tested my 6300 with 12 inch long 10 gauge DC power cables, and RF out going only through the LP-100A wattmeter then into a 50 ohm dummy load. I tested each band at 5 sec, 30 sec and 60 sec. I then waited 1 hr and repeated the test for 5 sec per band.

Flex 6300, RF Output Into 50 Ohm Dummy Load:

k3Tim

Joe,

Thanks for taking the time to gather this information and post it.  Informative.  The power didn't vary based on time, which is nice.
The DC pigtail had minimal loss no doubt.

Best Regards,,

k3Tim

Scott N8UMW

I see this is an old thread but must comment. It shows as being answered or resolved. I am a 6300 owner that does experience this problem. I have read all replies. I have tried a ten gauge short cable on my PS with no difference from the Flex supplied cable. I have full 100 watts on 20 and 10 meters. 85 to 90 at best on the other bands. This is both with the antennas and running short cables through a brand new Bird 43P to a dummy load with an Astron RS-70 PS at 13.73vdc with radio keyed at full power. I saw no change upgrading to the latest firmware/software. Am I correct in the assumption that I would have to send my radio back for a recalibration to get the power output it is rated to do? 

DrTeeth

That is similar to my findings (Flex 6300 here too), but my bands vary. You do realise that it is more likely that you will not get more power out, but just that the meter will read 100 on each band? That is my understanding of 'recalibration'. Just be happy that we can run 100% duty cycle modes at full power. If there actually is a slightly lower power out on a few bands it does not make any difference at the other end. I have much more faith in a meter that does not real ****-on 100W on every band anyway.

73 de Guy