FT-857d

Discussion in 'Amateur Radio Equipment Reviews' started by KI4KSY, Aug 6, 2009.

Thread Status:
Not open for further replies.
ad: L-HROutlet
ad: l-rl
ad: Subscribe
ad: K5AB-Elect-1
ad: Left-2
ad: MessiPaoloni-1
ad: L-MFJ
  1. KI4KSY

    KI4KSY Ham Member QRZ Page

    1st trip back to yaesu

    I am having a problem with the power output of this radio. It appears I can only get about 10- 20 watts average power output on some hf bands in ssb mode. I have tried it with 2 different watt meters into both a dummy load and an antenna. This problem is very apparent on 40 meters. I also tried the mic from my other 857 and that made no difference. As it is right now I can average 50 watts, but I have to set the mic gain to 100 and the processor to 90. I would like to be able to average 50 watts (100 watts PEP) without running the processor and yelling into the mic. 10 meters seems to work fine with the mic gain set to 50 and no processor it averages 50-60 watts, but 40 meters does not. As I go lower in frequency, I would think efficiency increases and if anything I would need to turn the mic gain down not up.

    (I have another FT-857D that has no problem averaging 50 +/- (10 watts) with the mic gain set to 50 and processor off on HF + 6meter. I tested this radio on the same watt meter and dummy load.)

    Please note I just purchased this radio 5 days ago. I would like it to work just as my other ft-857d does or be replaced.

    2nd trip to yaesu

    I sent the radio in with low output on 160 80 40 meters on lsb 3 days after I got the radio. 3 weeks later I get the radio back. Never fixed so with the help of a friend I did more testing… low output on all bands on lsb (20watts) and normal output on usb(50watts). ALC not working.

    Ft-857d
    PWR setting 100 W
    Mic gain setting 50
    Into Bird 250 watt dummy load
    With diawa cn101l watt meter (also power meter on the radio reads relevant to the external meter. Input power also relates to varying output.)

    1.82 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 60 watts
    Voice lsb : 20 watts
    Alc usb : NO
    Alc lsb : NO
    Single tone usb : 100 watts
    Single tone lsb : 100 watts

    3.8 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 50 watts
    Voice lsb : 15 watts
    Alc usb : NO
    Alc lsb : NO
    Single tone usb : 80 watts
    Single tone lsb : 80 watts

    7.2 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 50 watts
    Voice lsb : 20 watts
    Alc usb : YES
    Alc lsb : NO
    Single tone usb : 100 watts
    Single tone lsb : 100 watts

    14 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 50 watts
    Voice lsb : 30 watts
    Alc usb : YES
    Alc lsb : NO
    Alc fm : YES
    Single tone usb : 100 watts
    Single tone lsb : 100 watts

    21.3 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 80 watts
    Voice lsb : 20 watts
    Alc usb : YES
    Alc lsb : NO
    Alc fm : NO
    Single tone usb : 100 watts
    Single tone lsb : 100 watts

    28.4 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 40 watts
    Voice lsb : 15 watts
    Alc usb : NO
    Alc lsb : NO
    Alc fm : NO
    Single tone usb : 100 watts
    Single tone lsb : 80 watts

    50 MHZ
    Measured power output.
    FM: 100 watts
    Voice usb : 50 watts
    Voice lsb : 30 watts
    Alc usb : YES
    Alc lsb : NO
    Alc fm : YES
    Single tone usb : 100 watts
    Single tone lsb : 100 watts

    144.5 MHZ
    Measured power output.
    FM: 60 watts
    Voice usb : 35 watts
    Voice lsb : 20 watts
    Alc usb : YES
    Alc lsb : YES
    Alc fm : YES
    Single tone usb : 60 watts
    Single tone lsb : 60 watts

    Im sure they will fix the problem this time.(2nd time.) And because of that I was not even going to write this review. However, do the high probability I will not get to use this radio before my warranty expires second chances are out of the equation.

    Well i just got the radio back for the 2nd time and the output is correct, however I have to heat the radio up to get full output.

    Into a dummy load the cold radio starts off at 60 watts and after about 30 sec to 1 min it will slowly come up to 100 watts. What do you guys think of that?

    Its on its way back to yaesu in the morning and i am without radio [​IMG]

    My biggest disappointment is that they said they will not replace the radio.


    Just got it back. No luck now the radio has to heat up before reaching full output. And the radio is back to yaesu for the 3rd time. :)

    So this review is not going well.

    video review

    http://www.youtube.com/watch?v=ytPhsW1ZUgY

    <object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/ytPhsW1ZUgY&hl=en&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/ytPhsW1ZUgY&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>
     
  2. KA1MDA

    KA1MDA Ham Member QRZ Page

    Looking at the output figures you posted (especially the single tone figures), the radio appears to be puting out full output. You should not see more than 30 watts output on an average reading meter when operating SSB. If you see any more than 20-30 watts out in SSB, you're over-driving the crap out of the radio! I wouldn't even pay attention to the differences you measured between LSB and USB, as the radio is being over-driven so badly to get those numbers they are practically meaningless.

    Tom, KA1MDA
    www.ka1mda.org
     
  3. KI4KSY

    KI4KSY Ham Member QRZ Page

    The reason the usb and lsb was different was do to the fact my carrier point was off freq... After the factory aligned the radio the average power output for the radio on both usb and lsb was the same. (50 watts +/- 10). Yaesu even said it should be the same. So im glad I worried about that.

    The ft-857 uses 2 2sc2782 for power amplification in the hf-6meter section of the radio each device is linear to 80 watts 80x2=160 so 160 watts or more out of the radio would be “over driving”. So if I operate this radio at its designed power output of 100 watts with a modulated signal or a steady ahhhhhhhhhhhhh I should see 50 watts on usb and lsb on a good average power reading watt meter. And if 50 watts is my average power that means my peak to peak power is 100 watts. Hey 100 is less then 160 that means the radio is not being over driven.

    The point is that this radio has component after component changing value.

    I have another FT 857d that works perfectly. And the question to yaesu is why doesn’t this one work as specified.
     
  4. GM8UPI

    GM8UPI Ham Member QRZ Page

    I agree with Tom. Your 857 is functioning 100% correctly, just like my 857. I do not believe your assumption, that Average power is 50% PEP power, with an Ahaaaaa..... or single tone, is correct. A figure around 35% - 40% is what is normally used as estimate. The best way to measure your true SSB output level would be to use a true two tone input signal, and apply the % factor. I do agree that LSB & USB should be more or less identical, unless injection offsets are badly out.
     
  5. NN4RH

    NN4RH Premium Subscriber QRZ Page


    Unless you're using a good peak-reading wattmeter, you should NOT be seeing much more than about 30 watts indicated on the meter. Most power meters including the ones built into the radio and any tuners you're using are not measuring peak power, but some sort of average power, and that not very accurately. Your average power on SSB modes should generally be no more than the 30 watt range. If you're putting out much more than 30 watts average power then you're almost certainly overdriving the radio.

    Set the power level at 100 watts and adjust the microphone gain until there's only some ALC indication some of the time. Then look at the power meter. It will probably read around 25 or 30 watts on average.

    Put it in CW mode, set the power at 100 watts, and key the rig. In that case the power level should be reading 100 watts or close to it. If it is, then everything is doing what it is supposed to be doing.

    NO ! ! ! That is not how it works!


    I have two radios on my desk right now. An FT-897 and FT-950. With RF power set at 100 watts and the mic gain set so there's just barely ALC indication occassionaly under my normal voice, neither of them gives a reading more than about 20 to 30 watts output on either LSB or USB on any band, into either dummy load or antenna, using the averaging wattmeter in my Palstar tuner. However they both give 100 watts meter reading in CW mode.

    If I set the wattmeter to Peak Reading, then I get 100 watts meter reading on both LSB and USB.

    Just because my average-reading wattmeter only reads 20 watts does NOT mean the radios are broken. The radios are fine. The radios are doing exactly what they are supposed to. The wattmeters are doing exactly what it they are supposed to.
     
    Last edited: Aug 14, 2009
  6. WA6MHZ

    WA6MHZ Subscriber QRZ Page

    Whistle into it and see what happens.
     
  7. KI4KSY

    KI4KSY Ham Member QRZ Page

    Well it’s nice to know all of you guys have the same problem. Man it just makes me smile. I have 2 857’s and one works perfectly and the other i (WAS) a piece of junk.(yaesu replaced the radio and now it works as it should)

    Maybe im wrong if all of you have the same problem. But then Yaesu is wrong also because I just got a new radio back from them and the tech said he was sorry and that the radio was so far out of spec due to multiple components failing that they could not bring it back. So the radio was so bad that they sent me a new one. And the new one works perfectly. :rolleyes:
     
  8. KI4KSY

    KI4KSY Ham Member QRZ Page

     
  9. NN4RH

    NN4RH Premium Subscriber QRZ Page

    No. That's the sort of thing that can occur when someone tries to do some of those CB-ish "mods" or fiddles around with the service menu without knowing what they're doing, and screws up the radio.
     
    Last edited: Aug 18, 2009
  10. KE5SZY

    KE5SZY Ham Member QRZ Page

    If you just purchased the radio 5 days ago then you should have RMA'd it to the place you bought it from and considered it DOA.

    On a side note your power levels sound correct.
     
Thread Status:
Not open for further replies.

Share This Page