From cbfsb!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!uunet!mcsun!news.funet.fi!sunic!loke!lulea.telesoft.se!hakanl Thu Dec 5 17:29:41 EST 1991 Article: 11721 of rec.radio.shortwave Path: cbfsb!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!uunet!mcsun!news.funet.fi!sunic!loke!lulea.telesoft.se!hakanl From: hakanl@lulea.telesoft.se (H}kan Lennest}l) Newsgroups: rec.radio.shortwave Subject: Re: DX440 mod - how to Message-ID: <3858@lulea.telesoft.se> Date: 5 Dec 91 16:25:51 GMT References: <28343@mentor.cc.purdue.edu> Organization: Telia Research AB, Lulea, Sweden Lines: 42 swifty@tc.fluke.COM (swifty@tc.fluke.COM) writes: : In article <1991Dec4.163206.4247@milton.u.washington.edu> oberem@milton.u.washington.edu (Graham Oberem) writes: : >The following mod will remove the "chuffing" heard while tuning the : >Sangean 803/DX440 radios. : >5. Locate the 8-wire flat cable which runs from the circuit board above : : >6. Identify the second wire : > from your left in the cable. : > Bend this wire up and out of the way : : >9. Turn on the radio and enjoy the lack of "chuffing". : : This is amazing. If all the second wire does is cause chuffing, : why is it included in the design in the first place? Does anyone : have any insight into what this particular connection is SUPPOSED : to do? : : Thanks for the info, Graham. : I'll probably do this when my warranty runs out, but it's odd that this : modification apparently has no negative effects. : -- : Perry G. Ramsey Department of Earth and Atmospheric Sciences : dil@mace.cc.purdue.edu Purdue University, West Lafayette, IN USA : perryr@purccvm This signature gives you specific legal rights. You : N9LFF might have other rights that vary from state to state. The main purpose of the muting circuit that gets disconnected by this modification is probably to make the set silent when you hit the "search" button. I personally think that it is a feature to hear the "search" in operation. The reason why the set is "chuffing" is a result of a bad desing of the mute circuit: It is placed where there is a DC potential. It is placed after the volume control (less audiable if placed before). o /Hakan -- -------------------------------------------------------------------------------- E-mail: hakanl@lulea.telesoft.se | Hakan Lennestal, Telia Research AB Fax: +46-920-75490 | Aurorum 6 Voice: +46-920-75459 | S-95175 LULEA