开云体育"You can lead horses to water, but you cannot make them drink"-- This phrase seems to apply to the 817 group, since many YEARS ago, I posted a FIX for this oscillation, to eliminate blown finals, and enable safely leaving batteries inside, or operation WITHOUT the need for any "Ferrite Bead"!-All that is required is to disconnect the miniature coax cable at the input to the final PA board, and re-connect it afyer swapping shield and center connector polarity at one end of the cable! NO parts or adjustments needed! (Be SURE to remove batteries and other power sources before doing this alteration, and be very careful not to short or otherwise damage anything) You can probably find details in the site archives, with photos! All such oscillations should CEASE after the cable phasing is reversed!-73, KC3VO Sent from my Verizon Wireless 4G LTE smartphone -------- Original message -------- From: "'Robin Gape (lists)' list@... [FT817]" <FT817@...> Date: 11/29/2016 5:34 PM (GMT-05:00) To: FT817@... Subject: Re: [FT817] Tx oscillation on 432 MHz Andrew, and anyone else who never had the documentation or who lost it, the original Yaesu note is available, scanned, for information and fair use: https://www.dropbox.com/s/b9666ds7gsrt7ks/FT-817ND%20Important%20Note%20re%20430MHz%20and%20ferrite%20clamp.pdf?dl=0 Hope you find this useful. The official manual notes the presence of the ferrite clamp, but fails to tell one what to do with it! The supplied split-core clamp is about 31mm long, and 15mm diameter. One suspects that any similar clamp will probably do the job. 73, Robin, G8DQX On 29/11/16 21:06, andrew73@... [FT817] wrote: > I don't have any filter - I am the third owner of this radio and > although I received it in the original packing box, only the mike and > antenna bits were included.? I can buy a snap-on ferrite choke at an > electronics shop and will try that. > > Thanks > > Andrew VK1DA/VK2UH ------------------------------------ Posted by: "Robin Gape (lists)" <list@...> ------------------------------------ And for a great FAQ ( Frequently Asked Questions ) see http://groups.yahoo.com/group/FT817/database Some really good technical info at: http://www.ka7oei.com/ft817pg.shtml . Please note that your messages and files sent to this group may appear anywhere on the Internet or in print without notice or compensation. ------------------------------------ Yahoo Groups Links <*> To visit your group on the web, go to: ??? http://groups.yahoo.com/group/FT817/ <*> Your email settings: ??? Individual Email | Traditional <*> To change settings online go to: ??? http://groups.yahoo.com/group/FT817/join ??? (Yahoo! ID required) <*> To change settings via email: ??? FT817-digest@... ??? FT817-fullfeatured@... <*> To unsubscribe from this group, send an email to: ??? FT817-unsubscribe@... <*> Your use of Yahoo Groups is subject to: ??? https://info.yahoo.com/legal/us/yahoo/utos/terms/ |
