Yaesu Ft-80c Mods
. Related Information:. AD5X-. PA0FRI-ServiceManuals:.TheYaesu FT-7 and FT-7B were introduced in the late 70's / early 80's andstill enjoy a lively following because they are rugged anddependable.
Their receivers are free from the synthesizer by-productsassociated with some of the more modern radios and they areeasyto maintain Almost of the circuit boards are modular - easilyremoved for service. The radio also takes up little shack'shelf space'.This website offers twoadditional improvements to the many that have been published,those available in the Yahoo FT-7 Users Group, andthose found by searching the internet. Specifically,this website describes how to add an outboard digital frequencydisplay and an internal iambic keyer. Undoubtedly, other methodsof implementing these two features are also possible and the readersare encouraged to improve upon what's described herein.Boththe Yaesu FT-7 and the FT-7B use the same frequencymixing scheme.
Note: Asuitable enclosure needs to be built.A Radio Shacksmall box (cut out with an exacto knife) will do nicely.c) DL4YHF Display - ThreeVariants - CheckOut the FT-7Wolfgang Buescher - DL4YHF- designed an interesting and accurate 6digit display using thethat can either be homebrewed, or purchased on eBay as a kitfromRalph Van Dyke (the newer version - shown below). I've built2 of Ralph's kits, one for my andanother for this project. They both come with a nice plasticenclosure and blue LED's - really sweet! Unlike the unmodifiedChinese 6Digit Display, this device can be readilymanipulated to (optionally)detect and then subtractthe carrier oscillator frequency 'on the fly' with a few key presses,.
The digital displaycounter interface is already built into the FT-7B (Q1 - an emitter follower),probably somewhere on the backplane board. The base of thistransistor connects - through a small coupling capacitor and very shortlead - right to TP-1902 (pin 14), the output of the PREMIX oscillator.Toreplicate this circuit in the FT-7, a comparable driver needs to befabricated.
However, it would be extremely difficult to mountthis circuit in close proximity to TP-1902. I useda short piece of miniature coax from pin 6 ofthe mixer board (underside the chassis) to drive the modified buffercircuit, virtually identical to the emitter follower circuit used intheFT-7B.The software can be pre- programmed to include the LSB andUSB offsets to be subtracted, specifically 8998.5 khz and 9001.5 khz.When changing bands, the user must remember that 8998.5khz will be used for all CW work and for 40, 20, 15 and 10meter LSB and for 75 meter USB. Conversely, 9001.5 khz will be used for75 meter LSBand for 40, 20, 15 and 10 meter USB. Using the PGMbutton, toggle down to TABLE. Select either 8.9985or 9.0015. Enter a long keypress.
Select SUBtract and hold until it blinks. Release the PGMbutton.- The softwarecan be modified so that a single switch on the top of the displayenclosure will switch the mode of operation (i.e. CW/LSB or USB).In so doing,the counter will work only with the FT-7 / FT-7B. Use switch Position A for all CW,80 meter USB, 40 thru 10 meter LSB.
Use switch Position B for 80 meter LSB, and for 40 thru10 meter USB.A relay interface to the FT-7 / FT-7B frees theuser from remembering these 'rules'. The operated relay samplesthe carrier oscillator frequency and - after which a few buttonpresses - the display will subtract the carrier oscillator from thePREMIXfrequency. A top mounted switch will operate the relay anda push button will be required to program thecounter. Operate the SAMPLEswitch on the display and the actual carrier oscillatorfrequency will be displayed,. Using the PGMbutton, toggle down to SUBtract. Hold the display push button down until SUB blinks,. Release the PGMbutton (andthe display will show all zeroes),.
Release the SAMPLEswitch and the actual frequency will be displayed.d)Installation SuggestionsFor the and / or the Push ButtonConversion,the rear of the FT-7 / FT-7B is removed to install a. The Push Buttondisplay conversion also requires a minor FT-7 (External VFO jack) orFT-7B (display jack) wiring change.For the FT-7,here are the connections on the 5 pin FT-7 External VFO jack where theexternal display will connect:. 13 VDC - pin 5. Ground - pin 2.
VFO (coax) - pin 4. +8 VDC - pin 3. EXT 8V - VFO - pin 1Thisjumper between pins 1 and 3 is cut if an external VFO is used.Remove the jumper and the two leads, connect these twoleads together, insulate the connection and stuff the wires back intothe radio.
Theinternal VFO will not workif these two leads are not connected together.Leave the other leads intact. Run a wire from one ofthe 2 spare terminals back to the miniature relay connection on thesource follower counter interface buffer board.For the FT-7B,the digital display connections can be made directly tothe existing external display socket. No wiringchanges will berequired and n o interfaceboard will be needed - UNLESS you areinstalling the PUSH BUTTONconversion.The FT-7B has a buffered circuit already connected tothe PREMIXoutput. Here are the connections on the 7 pinjack to which the external display will connect:. 13 VDC - pin 7. Ground - pin 6.
Premix Output - pin 1. pin 3 - CW - not sure, print is blurry. pin 5 - LSB - not sure, print is blurry. pin 2 - USB - not sure, print is blurry.
Yaesu Ft-747gx Mods
pin 4 - 3.5 - not sure,print is blurryFor the PUSH BUTTONconversion, use either pin 2, 3, 4 or 5 for the push button relaycontrol lead.For theinternal keyer, mount both a SPST (normally open) push button switchand a 3 conductor miniature jack on the,running the wires up through the radio as shown. Note:The push button activates the keyer's command modeand is installed at the rear to avoid drilling holes in thefront. However, additional transistor switching circuitrycould be installed to 'repurpose' of one or more of the frontpanelcontrols (like the MARKer or Noise Blanker).I decided not to do this as I (very infrequently)use the keyer command button just to change the keyer speed.Remove the cover over the PAfilter board. In replacing the rear panel,ensure that nothing is pinched.For the FT-7 6 DIGITor DIRECTconversions, build the emitter follower counter interfaceboard that will buffer the PREMIXsignal sent to the counter. Reuse the output coaxialcable running to the rearmounted external VFO connection, reterminating it. Note: If you use afrequency counter, measure the carrier oscillator outputs at either pin7 or 8 on the IF Board.Setting the carrier oscillators for the PUSH BUTTONconversion precisely on frequency is not terribly important as the counter will measure the actual carrierfrequency which will be subtracted from the PREMIX frequency.For the DL4YHF conversion, the time baseofthe mustalso be set. You may calibrate the time base by firstcarefully tuning the FT-7 / FT-7B to aSSB station of known frequency - say, one that is being received onanother station receiver - and then adjusting the time base until theFT-7's display matches that of the other, verified on another, knownaccurate station receiver.
Alternatively,you can zero beat the PIC's 20 Mhz time base with a good receiver tunedto 20 Mhz, perhaps zero beating it against WWV, if you can receive it.Note: TheChinese 6 Digit LED counter has already been set at the factorY anddoes not require any readjustment.c) Modified Software for theDL4YHF CounterThe software forthe modified DL4YHFcounter is finished and will be available from Ralph Van Dyke shortly.d)Internal Iambic KeyerI decidedto purchase the unit that I've used in other projects. The Jackson HarborPress keyer board is mounted on the P/Cboard formerly used for the FIXED frequency. Thisboard wasstripped of all its components, the Jackson Harbor Press keyer mountedwith 1 stand-off screw, and connected with 30 gauge wiring to theproper pins on the stripped FIXED board /.Theconnects to the proper points in the radio. This way, thekeyermay easily be removed from the radio, if necessary.
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Mods.dk - Articles for Yaesu 'FT-80'Main MenuModification database:Articles for Yaesu 'FT-80'UploadedDescription14 Oct 200802 Mar 2007This forum message list include all message for that is related to FT-80, this include message that also is related to articles. If the message is relate to an article, the article can be selected next to each message.DateAuthorSubject1.20 Jun 2015michel(0)2.13 Jun 2015michel(1)3.24 Jan 2015Alexander Petrov(0)4.18 Mar 2008Agung(0)5.18 Mar 2007Tafa Diop(2)Note that the message is not related to any article.Do you have any tricks, modifications or constructions for homebrewed equipment that are not on mods.dk, If you prefer to be anonymous write it in the message.Yaesu Menu© Copyright mods.dk 1996 - 2019.