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Re: CQWW VHF
¿ªÔÆÌåÓýHi Zack, ? I believe that the circuit is actually protected against shorts as Q3013 and R3045 work as a current limit to prevent it putting too much current into the antenna. ? I think that Q3008 and Q3009 are used to select the actual voltage to put on the ANT line so one puts about 12V onto the line and the other puts a reduced voltage of around 8V onto it. My guess is that the ANCV line controls the voltage and the ANNG is feedback as to what voltage is being fed to the antenna. ? Also, if you have the antenna selection on anything except ATAS in the menu, then I think the above circuit would be inhibited as it doesn¡¯t require any voltage on the antenna cable unless ATAS is selected. ? I use a mag loop antenna on my FT897 regularly, which has a primary loop connected directly across the coax, and have no problem with it and its circuitry is basically the same as the 857. Hence I don¡¯t think the matching section on your 6 m antenna has been the cause of the problem and I think I would start looking elsewhere. ? Maybe you can literally ¡°sniff out¡± where the smoke escaped from or find the burnt component to get an idea where the problem is ? Good luck with it. ? 73¡.Eric VK2VE. ? From: [email protected] <[email protected]> On Behalf Of Zack Widup
Sent: Tuesday, 19 July 2022 13:27 To: [email protected] Subject: Re: [FT-857] CQWW VHF ? That could be. I did come to realize something. My 6 meter Yagi has a hairpin match across the input - and the coax. At DC, that would look like a short to whatever the coax is connected to. If the radio was trying to put 12 volts on the 6 meter antenna line, it would've been shorted. I can't figure out what was damaged, though. Q3006 is good. The inductors between the Q3006 collector and the HF antenna connector are OK. When I try to transmit now, there is 12 volts on the emitter of Q3006, but it doesn't turn on 12 volts to the ANT line. If it was doing that before, something was damaged. ? I did verify that all the the final output transistors are OK and that there is RF drive at the correct frequencies from the MAIN board to the PA board.? The? final output transistors have 12 volts on their collectors and, on transmit, have the correct bias voltages on the base terminals. I can't figure out yet why there's no output. ? 73, Zack W9SZ ? On Mon, Jul 18, 2022 at 8:09 PM Eric van de Weyer <groups.io@...> wrote:
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Re: CQWW VHF
That could be. I did come to realize something. My 6 meter Yagi has a hairpin match across the input - and the coax. At DC, that would look like a short to whatever the coax is connected to. If the radio was trying to put 12 volts on the 6 meter antenna line, it would've been shorted. I can't figure out what was damaged, though. Q3006 is good. The inductors between the Q3006 collector and the HF antenna connector are OK. When I try to transmit now, there is 12 volts on the emitter of Q3006, but it doesn't turn on 12 volts to the ANT line. If it was doing that before, something was damaged. I did verify that all the the final output transistors are OK and that there is RF drive at the correct frequencies from the MAIN board to the PA board.? The? final output transistors have 12 volts on their collectors and, on transmit, have the correct bias voltages on the base terminals. I can't figure out yet why there's no output. 73, Zack W9SZ On Mon, Jul 18, 2022 at 8:09 PM Eric van de Weyer <groups.io@...> wrote:
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Re: CQWW VHF
¿ªÔÆÌåÓýHi Zack, ? Looks to me like it¡¯s the circuit which supplies the two voltages to the HF antenna socket to drive the ATAS antenna up and down. The line labelled ANT ends up at the antenna connection on the far right and is DC coupled to it. ? 73¡.Eric VK2VE. ? From: [email protected] <[email protected]> On Behalf Of Zack Widup
Sent: Tuesday, 19 July 2022 02:51 To: [email protected] Subject: Re: [FT-857] CQWW VHF ? I have been looking at the service manual for the FT-857D and I may see a potential problem. I am not at home now, so I can't check things out. But on page 8 of the service manual, under the PA Unit block diagram, there is a little section labeled "Q3006, etc. 2SB1134 2SA812 2SC4154 ANT DRIVE" with an input labeled ANCV and an output labeled ANNG. The circuitry for this shows up on the schematic on page 55 close to the left side of the page, a little above the center. WHAT exactly does this part of the circuit do? ? 73, Zack W9SZ ? On Sat, Jul 16, 2022 at 6:57 PM Zack Widup <w9sz.zack@...> wrote:
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Re: CQWW VHF
I have been looking at the service manual for the FT-857D and I may see a potential problem. I am not at home now, so I can't check things out. But on page 8 of the service manual, under the PA Unit block diagram, there is a little section labeled "Q3006, etc. 2SB1134 2SA812 2SC4154 ANT DRIVE" with an input labeled ANCV and an output labeled ANNG. The circuitry for this shows up on the schematic on page 55 close to the left side of the page, a little above the center. WHAT exactly does this part of the circuit do? 73, Zack W9SZ On Sat, Jul 16, 2022 at 6:57 PM Zack Widup <w9sz.zack@...> wrote:
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Re: CQWW VHF
I have all homemade beans. They have been optimized with Yagi Optimizer. I built them so they can be transported in a car disassembled and then rapidly assembled on site. I have been using them for about 15 years. On Sun, Jul 17, 2022, 7:38 AM Joshua KJ7LVZ <joshuajayg@...> wrote: Man, that's really a bummer.? When the magic smoke comes out it never feels (or smells) good.? Please share the failure with pictures when you get it figured out.?? |
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CQWW VHF
I went to my favorite hilltop in EN50rl for CQWW VHF,
managed to get the 6 and 2 meter Yagi antennas set up in the hot sun (the 6 meter Yagi is BIG),
hooked everything up and it seemed to be doing fine. Antennas were
working and SWR was good. I called several people over about a half an
hour on 6 meters with my FT857D. None of them seemed to hear me. I was
only running 10 watts as a QRP Portable Hilltopper. Then I saw smoke
come out of the rig and then no power came out. It still received OK. I
checked both 50 and 144 MHz and had no power output on either band. So I
took everything down and went home (a 45 minute drive). The
rig did quite well up till now. I used it in the June VHF contest. I
don't feel like digging into it right now to see what went bad. I'm sure
I can repair it if I can get the parts. I only had today from about 1 to 6 pm CDT to participate. I can't be on tomorrow. But I'm sad that I didn't make even one QSO. 73, Zack W9SZ
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Re: FT857d with external SWR/POWER Meter
Thanks for the reply I found the instructions and yes it is a Chinese knock off... as of now it works fine with swr setting but will calibrate it later.. 73 Russ ? ? ? Russ Ouellette rjo601@...
On Thursday, July 14, 2022 at 09:28:18 PM EDT, J.D. Barron <jeter.d.barron@...> wrote:
Look up the information on the LDG forum in the files section or Google it. The one on Amazon is a cheap Chinese knock-off of the LDG unit. The operations manual also has a section on it as I recall, IHSST (I Have Slept Since Then) so don't hold me to it. KE4MD |
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Re: FT857d with external SWR/POWER Meter
Russ,
toggle quoted message
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Can you give us a link to the Amazon item? 73, Cameron?
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Re: FT857d with external SWR/POWER Meter
Sorry I have not replied... The swr meter is from Amazon.com. I believe it is a setting in the Radio.. but can't adjust the meter for 100 watts.
for full deflection.... there was no instructions that came with it. Only adjustment is on the front panel a screw to adjust to 1:1 .... if this helps.. Thanks.. ? |
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Re: YT-100 Tuner Failed (apparently) - Need replacement Cable
Dennis Yard
Ron,
After troubleshooting, I think you might be right.? ? I found a bent pin on the cable which may have shorted out the input voltage.?? Trying another cable yielded no power up of the tuner either.? ?Also tried another tuner with no power up. Time for an RMA to have it looked at.? Im not so sure i want to fool with the tuner and smoke it too.? Dennis N1TEN ? |
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Re: FT857d with external SWR/POWER Meter
¿ªÔÆÌåÓýActually, there should be no output on SSB until you talk or supply some other form of modulation. AM isn't rated at 100 watts, it's only rated at 25 watts. Check your settings, it sounds like it's set for ALC instead of power out.Randy (KE5EOT)
ARRL, QCWA, ARES, RACES, ROWH
On 7/13/22 12:05 PM, John wrote:
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Re: FT857d with external SWR/POWER Meter
I think your wattmeter may be lying to you, check your O/P against another meter and of course a dummy load. My 857 is 15yrs old and only puts out 100W, unless you have tweaked it. John VE7KKQ On Wed, Jul 13, 2022 at 3:42 AM Ted via <th916=[email protected]> wrote: At the 100-W setting my meters tell me my 857 typically puts out about 120 watts. If The maximum capacity of Russ's meter is 100 watts this could explain why it's pegging at the 100 watt setting. |
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