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Speech Processor
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Is the speech processor just on/off? I don't see anywhere to adjust the compression level. Thanks
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Discriminator Meter Off Center
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Hello, I just got my first FT-847 a week ago. I notice the discriminator always pulls to the left even with no signal. I did adjust the ref osc as it was off freq a bit. Looks to be about 900hz off. I looked through the service manual briefly but didn't see a way to center it. Thanks K9CZ
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Interesting bug...
Hi folks, With the return of sunspots and randomly good propagation, a short note which you might want to know about. I heard early today that propagation on 10 meters was open from the West Coast to the mid-west, where a number of 10 meter FM repeaters reside. I've worked some of them in the distant past (prior cycle), so went listening. The trusty 847 automatically dialed in the -100khz offset as I poked in the 29.620 FM frequency. Nice. Later this afternoon a fellow ham asked for a radio check for his new 10 meter antenna, so we agreed to meet down in the SSB portion of the band. Punched in the new frequency, tapped SSB, and keyed up. He repeated his call. No contact. Finally I noticed that the 847 was still in repeater mode (even though I was clearly in SSB), therefore transmitting on the wrong frequency. Pushing the RPT button did not work to turn off RPT. I had to switch back into FM, turn off RPT, then switch back to SSB. {sigh} You probably already know this, but it bit me today. Greg KO6TH
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I need help as I have no power on SSB (all bands), whereas FM is fine, whenever I transmit on my FT-847. Receiving SSB signal is fine. I've confirmed this problem on a watt meter to a dummy load. Is there a relay to change modulation mode that might be stuck ? 73 de Yono - YD0NXX
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Hi all, I have a rather strange issue with my '847 that I haven't yet figured out the cause for: It doesn't receive or transmit between 420 MHz and 459..9995 MHz. Background info: I'm 3rd owner of my nearly mint condx. My understanding is that it has never been modded or altered in anyway. An examination of some of the circuit boards shows no signs of tampering/repair or component damage. The radio functions perfectly in every sense, transmits and receives in all 5 modes without issues on all amateur bands (except 440 MHz band of course) and receives perfectly fine on HF and VHF general coverage receive, and receives perfectly fine at 460 MHz up to 512 MHz. No other anomalous functionality except that I just discovered during my trouble shooting session that I cannot enable the Alaska 5167 kHz emergency channel in the menu, and that my radio will transmit at 460 Mhz and up. That last bit piques my attention as my understanding is that these radios cannot transmit out of band unless someone has done a mod? When I select any 70 cm frequency and key the radio, the speaker audio cuts off normally and I hear the cooling fan step up in speed from it's normal stand-by cooling speed like it normally does on any other band. "Transmit" appears on the display, but no PO level, nothing, no matter what mode I use. Using a couple of dual band radios confirmed to be working (I hear them perfectly on a pair of Icom R7000's) there is a definite gap between 420 MHz and 459.9995 MHz where nothing is heard or can be sent. But the moment I go to 460 MHz and higher it will receive and transmit. I do not hear a change in the receive static in the affected frequency region as I scroll up in frequency. I've performed the CPU reset with no resulting change in behaviour. Owned the radio for over 5 years but i've never used it on 440 MHz before so I do not know how long this issue has existed. Any ideas before I break out the magnifying glasses and schematics?
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MH-36D Microphone puzzle
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Hi folks, I've been using an MH1-B8 microphone for a while (few years), substituting for the rig's original MH-36D which had the disintegrating rubber cord problem. Following up on recent suggestion on the Amsat forum, I ordered and received a replacement cord meant for the MH-36 with the RJ plug. Cut off the RJ and connected the 8-pin round connector, and it seems to work, including the DTMF keys which is why I wanted to do the repair. But, I'm getting reports that my audio has a sort of hum on it, and the volume is rather hot, even with the microphone gain turned all the way down. I double checked the wiring, and I think it's right. The new cable has 6 wires instead of 7, so left the missing "Fast" line unconnected on the 8-pin. The MH-36D has no such button, so no loss there. The 2 grounds (mike and other) are connected together at the 8-pin connector; there's no "shield" on the cable, nor was there one on the original. Is this behavior - the hum and loudness - "expected", or is there something else going on? I see what appears to be a small potentiometer inside the mike, just above the connector. Does that need to be adjusted? What is it for? I haven't touched it as yet, but I'm not the radio's original owner. Thanks, Greg KO6TH
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FAST button not working through mic jack
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Well now that the UHF transmit problem was resolved (thank you again to everyone), my next issue is the FAST function does not work from the microphone or by shorting the appropriate pins on the mic jack. When I press the FAST button on the front panel the icon shows up and tuning increases as expected, so it is working from the panel. I'd like to resolve this as I need to align the SHIFT control and I can't get in to the adjustment menu without the FAST button working on the mic. Max
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FW: Cable as shown is what you need
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From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 21:41 To: Andrew Lenton Subject: Re: Cable as shown is what you need Some of the satellites have SSB uplink on UHF. Whether I use them or not at least I know the radio is capable. Thank you for all the help along the way Andrew, I gained lots of experience in troubleshooting from your instructions. Max On Sat, Aug 6, 2022 at 4:20 PM Andrew Lenton <a@...> wrote: Hi Good news I guess you mean bands, I would trust the meter on the radio, and the current going into the radio! Well done 73 Andrew 2020 here of to eat a sandwich From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 20:27 To: Andrew Lenton Subject: Re: Cable as shown is what you need I've returned the tx according to the service manual. RF meter on radio now showing 50w. I think the external meter is not accurate on UHF. Anyway I am very happy with the results. Now I can work all the birds! On Sat, Aug 6, 2022, 3:17 PM Andrew Lenton <a@...> wrote: Progress, so there were two faults Q4001 was put on by someone else chasing the fault, so we are back to chasing the low RF input So with -30 dBm in and 5 Watts out we have 37dB gain I much prefer that! So we are only looking for 10dB extra gain. To get 50 Watts Check what is coming in on VHF? Should be -20dBm ish? 73 Andrew From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 20:03 To: Andrew Lenton Subject: Re: Cable as shown is what you need Okay so I just unsoldered Q4001, cleaned the 4 tabs, resoldered and now I am getting 5W out on the meter with the RF power up all the way On Sat, Aug 6, 2022 at 2:58 PM Andrew Lenton <a@...> wrote: I thought you were not getting anything UHF TX wise, what is the level on VHF TX? I also thought you were not getting anything out of the UHF VCOs’ or do you have signal now there? -30dBm seems low, but I may be wrong -30dBm to 47dBm (50 Watts), is 77dB gain, on the PA board I am sure with that amount of gain it would hoot! So I feel it should have more coming in hence check what the VHF side is doing level wise? I have used professional DTV amplifiers, that go from -15dBm to 300 Watts (54dBm), but these are precision engineered and weigh over 150lbs !! 70dB gain 73 Andrew From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 19:33 To: Andrew Lenton Subject: Re: Cable as shown is what you need Nothing. I think Q4001 is shot. I'm getting -28.9 dBM om the input of Q4001 and -69.9 dBM on the output On Sat, Aug 6, 2022 at 2:15 PM Andrew Lenton <a@...> wrote: Turn the gain to max see if you get any RF coming out From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 19:13 To: Andrew Lenton Subject: Re: Cable as shown is what you need I even tried using the HT to inject a signal on the low power setting. Nothing. On Sat, Aug 6, 2022 at 1:59 PM Andrew Lenton <a@...> wrote: Interesting, not sure how much level it requires? You could measure the VHF side, see how much TX IF level is, the problem is if it say 50 to 100mW, it will damage the SA without an attenuator 73 Andrew From: Max Donoghue [mailto:ve3tmt@...] Sent: 06 August 2022 15:01 To: Andrew Subject: Re: Cable as shown is what you need Just tried a direct coax connection. No change. HT is picking up the signal from the Tiny SA no problem though. On Sat, Aug 6, 2022, 9:47 AM Andrew <a@...> wrote: Get Outlook for Android
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Hi the SAT button on and off a few times! Check Q2017 is switching as this will kill off the UHF RX and TX LO this should be working as RX is working can you confirm this, tx on a hand held or signal generator D2017 the anodes of the diodes are switched separately for TX and RX, confirm the LO is on cathode of D2016, then follow the LO through the circuit path to the TX LO O/P via Q2039 OK TP 4 to TP 7, is the supply to the VCO, pulled on by a PNP transistor in Q2015 to 18. OK we have VHF 1 + 2 and UHF 1 + 2, and 4 VCO, I suspect two are for TX and the other two for the RX VCO as they will probably be different frequencies! Or slit frequency operation (not sure here) or when TX and RX are used simultaneously in SAT mode? 73 Andrew Sent: 22 July 2022 19:34 To: Andrew Subject: Re: If low at O/P then trace back D2016 switching? Went digging into the PLL board. I'm getting 3.66V at TP2003 in TX D2019 is switching as expected, one line high for HF, one for VHF and one for UHF. All three lines tested fine.On the underside of the PLL board, I am getting 7.9V on TP2006, but not TP2007 which leads to Q2018. On UHF I'm getting 7.9V on pin 2 of Q2017 but nothing on pin 2 of Q2018 check if there is something there on RX On VHF I'm getting 7.9V on pin 2 of Q2016 but nothing on pin 2 of Q2015 check if there is something there on RX
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Looking for outer trim piece
If anyone has an FT847 they are parting out, I am looking for the outer trim piece from the unit. Mine arrived cracked during shipping. Thank you for looking Kent K9EZ
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I see this connector in the back of the faceplace, it is not connected to anything. What it is function?
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Hi As I no longer have an FT847 if anyone gets the chance, can they measure what they get on the following: MD2003 Pin3 MD2004 Pin 3, base of Q2014, collector of Q2014, Base of Q 2022, Collector Q2022 and Q2031 on UHF TX and RX Just need relative levels into a Spectrum Analyser, a small nano Spectrum Analyser. Next time you take your rig apart, or have nothing else better to do! 73 Andrew G8UUG
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Mars for Serial 1C470057
Does anyone have one of those rigs? I cant get it to works on 60m and 27Mhz. Have tried the options found searching and nothing. It was purchased in Japan.
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Hi FT-847 fans!! This is Carl, KO4SSA. I just purchased a used 847 on eBay, from Japan. I’m wondering how to modify for US bands. As delivered only TX 144-146 and 430-440. I’ve searched high and low on the the web, including Colin, G1IVG’s page, and emailed him!! Haven’t heard back. I’ve tried several solder joint configurations and will not TX on 146.52 or 445000. About to give up. Is the Japan stuff transmit range burned into EPROM or something???? Colin lists several HF coverage configurations and I am able to transmit on 14.550!! (into dummy load of course) I point out as evidence that changing the solder jumpers did do SOMETHING. Also, initially the cross-band repeater item was not available on the menu and now it appeared. More evidence that changing the jumpers did something. Thanks Carl
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Hi Max, OK you need to check J3006 TX I.F., and J3007 TX LO, they are common to VHF and UHF, The LO is the bit that changes frequency, check it does and the level is the same on VHF and UHF, if all good then Q3002 is looking suspect. Not sure of the actual frequencies, or if the LO is higher than the IF or lower, The IF can be 1.8 to 30MHZ, no idea what frequency is used for VHF and UHF say 15MHz, then then the LO would be 425 MHz for 440 MHz 73 Andrew
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Hi Everyone, I received the below in my email today. I hope somene can help the gentilman. :) I'll give the group first dibs on this, then it'll be going up for grabs on QRZ.com. Do NOT contact me unless you have no luck with him. FT847es For Sale Inbox F M (Dan) Daniels <w5kkq@...> 2:36 AM (10 hours ago) to N4MAV@..., kubotadan@... Russ, This is W5KKQ , Dan Daniels I am ok in QRZ I saw the Ft847 groups I/O page. I have an FT847es for sale. I have Wet Age-Related Macular Degeneration in both eyes. My right eye is almost blind.I cannot read the dials on the FT847es. So I had switch to a Flex 5000a so I have a 32" screen. I bought it from a neighbor, KT5U, he bought it new. I have the original box, and packing that came with it. The push button mike that came with it, and the 12VDC power cable that came with it. I have a programing cable that goes with it. It is clean and the box is still in great shape. I am asking $750.00. If you will allow m to post on the FT847 Groups I/O page or if you post it for me. This is a special radio. I live near Dallas and looking for some hams interested in AMSAT. Thanks, Russ for reading this email. If you think any of the FT847 community will be interested in this radio I will send you pictures and the serial number. kubotadan@... Best 73's Dan Daniels W5KKQ
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Looking for a good set of schematics with voltage references. My 847 has no output on UHF band, known to me when I purchased it. I'm aware of the issue with the leads on the UHF module losing contact, but I checked that and resoldered just to be sure but did not resolve the problem. Time to start looking elsewhere. All suggestions on what to check next are welcome. Thank you Max
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Talk back or moni
Greetings, I was wondering and it is possible the question has been asked and answered, so I am sorry then. The FT 847 moni feature for SSB is nice. Is there a way to enable this feature for AM and FM as well so one can monitor his modulation? I had a issue a while ago that I thought was the radio but ended up being the desktop microphone. I was even thinking of seeing if a external modulation meter could be used. Thank you. 73' Mark KC3TNO
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File /FT-847 Mods/TCXO_9 mod FT847 ON6AB.pdf uploaded
4
#file-notice
The following files have been uploaded to the Files area of the [email protected] group. /FT-847 Mods/TCXO_9 mod FT847 ON6AB.pdf By: on6ab <bruno.beckers@...> Description: Easy and clean upgrade with minimal impact on the FT-847 circuitry.
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Image Name
Sat 8:39am
Sat 8:39am