6500 power

Stefano - W2WTZ

The power meter on my 6500 shows a maximum of 85W. I checked with LS2K4 Wattmeter that is a little bit more accurate than a bird and tha value is correct. Power supply gives 13,53V. Why my Flex doesn't give full power ouput? The specifications says 100W if am not wrong. I read some posts on the same matter but I didn't undestood if this is a general problem, there is a fault on my 6500 or what else. 15W missing on 100W it's a lot...

Mack

Stefano, The proper voltage is 13.8 volts at the terminals on the rear of the Flex radio when transmitting. Also, are you transmitting into a 50 ohm non inductive dummy load? Do you have an ATU disengaged? Please confirm your test conditions and perhaps we can offer a bit more info. Mack W4AX Alpha Team

G8ZPX

Stefano,

Clearly the TX output will vary a little from band to band, but 15% down sounds way too much. What bands are you testing on and is it a purely resistive dummy load?   A good thing would to to check/plot the output on all bands and come back with more detail. 

My 6300 also varies by about 4% from one band to the next. However, at no point do I actually see 100W or better output, even after increasing the DC power input to 14.2VDC at the terminals whilst TX engaged.

73 de Steve G1XOW

Ross Biggar

I have the same problem Stefano, I just checked my 6500 into a dummy load and it gave similar results to yours. I was interested to check as an amp I am interested in need 70plus watts for full power and I wanted to amke sure I had enough to drive it.
Regards
Ross
ZL1N/ ZL1wn

Stefano - W2WTZ

The voltage 13,53V is at power supply output checked with a Fluke 1000€ industrial multimeter quite accurate. I checked with 50 ohm Nokia Ericcson dummy load. 85W in on 20meters band.
A friend of mine with 6300 (same wattmeter) has 95W in 20 meters - 102W in 6 meters - 89W in 40 meters - 87W in 80 meters. At lunch time I will make a measure on each band. testing in FM or SSB pressing Tune doesn't change anything. ATU is disengaged. 4% is acceptable but I think that 15% less is a little too much.
I will check the voltage at the Flex input plug too, but the power cord is the original supplied by Flex.

Stefano - W2WTZ

Flex specifications says that the 6500 requires +13.8V DC nominal ±15% and gives 1-100W.
13,8 minus 15% is 11,73V. My power supply is 50A, so the voltage remains quite constant under load.
Following the specifications I should not have any power supply voltage problems that affects the power output. It's not easy to check the voltage at Flex plug, I think that 13,8V is at the power supply output, the power cord is standard and supplied by the producer...
Dear friends do you think that it could be very useful to all of us an information of correct power output checked by Flex laboratory for every band, complete with the testing conditions,  so we can compare our units?

HCampbell WB4IVF

You really should check voltage at the radio.  It's not too hard and could save you a lot of unnecessary troubleshooting. A little resistance at the connectors could be significant. 

W9OY

DDUTIL reports out the radio's voltage to the nearest  0.1V via the API.   85/100 is about half a dB loss, not a big deal.

73  W9OY

W5XZ - dan

my 6500 is like yours, Stefano...73

Jim Gilliam

What were the conditions? Did you check the power out into a dummy load or did you check it while connected to an antenna. It is possible you are losing 15 watts both due to SWR loss as well as tuner loss. Also, common mode current can cause erroneous readings. It is best to check your power output under ideal conditions before forming any conclusions.

Jim, K6QE

Rob Fissel

Came here to say this. Also, the FlexMeter application for Windows will also tell you your voltage at the terminals. We have no idea how long of a run you have between the PS and the radio, the gauge of the wire, etc. Measuring the voltage at the power supply is not a good indicator of what the voltage is at the radio terminals. 

K4MT

Just checked my 6300 88 watts and actually goes up to 90.5 on 10 meters

Stefano - W2WTZ

Jim, I wrote that I'm using an Ericcson dummy load...........
Thank you Lee and Rob for the suggestion. I was in a trouble how to check the voltage at the radio. On Flex HW manual page 34 is written that to have maximum wattage I have to provide 13,8VDC at the radio. After dinner I will check and post a report on each band.

Rob Fissel

Yes, 13.8VDC under load at the radio, not idle.

Stefano - W2WTZ

I adjusted the power supply voltage to 14,3VDC, under TX on the radio I read 13,8VDC with DDutil.
I connected to antenna 1 a dummy load and I push ptt with slice in FM.
Here is the ouput power on center band :
6m 87W
10m 95W
12m 93W
15m 93W
17m 91W
20m 87W
30m 89W
40m 87W
160m 87W

Keeping the PTT pressed, after 2-3 seconds the readings decreases of some W, so the values above are optimistic in the best possible situation. The RF Power meter in SSDR is accurate.
I think this radio should be declared 90W and not 100W. I don't think my 6500 has a problem, becouse I read in this and other discussions that most of us noted the same problem. I would be grateful to have an official point of view from Flex and if possible the values they measure on their laboratory for comparison. If instead my unit has a problem do I have to open a ticket?

Stefano - W2WTZ

13,8 VDC at the radio UNDER LOAD

Stefano - W2WTZ

Sorry I forgot: no ATU of course

Tim - W4TME

I would open a HelpDesk ticket so we can investigate further.

KC2QMA_John

Same for me too, I Cannot achieve 100W @ 13.8V into 50 ohm load?

Looks like pwr foldback issue because sometimes when I key the radio for less than a second the meter in PSSDR will show 100W then quickly falls back to 85-90W? Seems to have started with 1.8?

K4MT

I am going back to 1.7 as I see strange behavior on power output and SWR.  I was in an Hour QSO and started out with 1:1 SWR and full power and after about 45 minutes SWR started reading 3:1. I put my digital SWR meter between radio and amp and SWR was still 1:1 but smartsdr showed 3:1

W9OY

My suggestion would be to upgrade to 1.8.4

73  W9OY

K4MT

I was on 1.8.4 now back to 1.7 downgrade in progress

Stefano - W2WTZ

I am on 1.6.21.159

Stefano - W2WTZ

On 20m SSDR swr is 1,7 while on digital wattmeter is 1,81

K4MT

Just finished downgrade and now TX power has gone from 88 to 98 watts into a dummy load with short cable.  SWR is  stable now when in amp as before it was moving around before.

Stefano - W2WTZ

where is possible to find 1.7 ssdr? On download page I see 1.8.4 only...

Stefano - W2WTZ

Ok found 1.7.30

KC2QMA_John

Stefano let us know if SWR & Power return to normal with 1.7

Jay Nation

Gary / K4MT
Could you also, retest the output using Flexmeter.exe  and report both peak and average power readings, and also the two supply voltage readings seen, when measuring the output power?

Flexmeter.exe should be available at ...

https://www.dropbox.com/s/igsnaxr91y8lhga/FlexMeter.zip?dl=0

I noticed that the above download link is for the earlier release of FlexMeter.

There was also a later release FlexMeter-1.1.0.1 that added the ability to display power as dBm and watt units, it also corrected the PA temp values that were broken due to changes in SmartSDR, a few upgrades later.

I found my download copy, and parked it at ...

http://www.sdrgadgets.com/FlexMeter-1.1.0.1.zip

For safe keeping.

Enjoy! 

,
73, Jay - NO5J
 

Stefano - W2WTZ

Quick check on 20m - 40m 10m no difference, but now I'm passing through the Acom amplifier in standy, maybe some W are lost. Tomorrow I will do the test in same conditions as today. I tried to increase voltage + 0,4V but I don't see visible differences.

K4MT

I just did more testing with amp and without back on 1.7.  My system power and SWR looks stable now but will do more on air tests tomorrow.