开云体育

Shrill noise on power up !!

Sourav #20943 开云体育 I get a “sharp shrilling tone” while the Bitx’s vol.on/off switch is toggled on ?!!….just beginning part about 2mm after which its normal sweep of the Rx volume up/dwn. How to stop it. …though the radio’s working fine & am getting a 9-10w o/p ? 73s, vu3cgb ?
Sourav #20944 开云体育 I mean in the HFSigs Bitx40 rig… ? toggle quoted message Show quoted text From: [email protected] [mailto:[email protected]] On Behalf Of Sourav Sent: 28 January 2017 03:24 PM To: [email protected] Subject: [BITX20] Shrill noise on power up !! ? I get a “sharp shrilling tone” while the Bitx’s vol.on/off switch is toggled on ?!!….just beginning part about 2mm after which its normal sweep of the Rx volume up/dwn. How to stop it. …though the radio’s working fine & am getting a 9-10w o/p ? 73s, vu3cgb ?
John Backo All Messages By This Member #20986 Audio feedback? If I were to guess, I would say that your power supply is not stout enough. Put an indicator LED at the power supply and see if it dims or flickers during transmit. If so, you need a heavier power supply. Another possibility is feedback in the microphone circuit during power-up. Probably the same solution or perhaps isolation. Is there feedback when the mic is held close to the speaker during receive? That would indicate a poor PTT connection. See if the switch is flaky. john AD5YE
Sourav #21037 No John...my pwr supply is an Alinco DM330FX. No mic feedback & ptt also well connected. I guess the vol ctrl on/off pot is faulty...will replace to see if still the problem persists !! 73 Sourav- Vu3Cgb toggle quoted message Show quoted text -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John Backo via Groups.Io Sent: 29 January 2017 05:49 AM To: [email protected] Subject: Re: [BITX20] Shrill noise on power up !! Audio feedback? If I were to guess, I would say that your power supply is not stout enough. Put an indicator LED at the power supply and see if it dims or flickers during transmit. If so, you need a heavier power supply. Another possibility is feedback in the microphone circuit during power-up. Probably the same solution or perhaps isolation. Is there feedback when the mic is held close to the speaker during receive? That would indicate a poor PTT connection. See if the switch is flaky. john AD5YE
Ken All Messages By This Member #21038 I had to replace the volume pot a week after receiving the BITX40. After a week of use I found the pot was becoming intermittent. 73 Ken VA3ABN toggle quoted message Show quoted text On Sun, Jan 29, 2017 at 8:57 AM, Sourav <sourav.relja@...> wrote: No John...my pwr supply is an Alinco DM330FX. No mic feedback & ptt also well connected. I guess the vol ctrl on/off pot is faulty...will replace to see if still the problem persists !! 73 Sourav- Vu3Cgb -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John Backo via Groups.Io Sent: 29 January 2017 05:49 AM To: [email protected] Subject: Re: [BITX20] Shrill noise on power up !! Audio feedback? If I were to guess, I would say that your power supply is not stout enough. Put an indicator LED at the power supply and see if it dims or flickers during transmit. If so, you need a heavier power supply. Another possibility is feedback in the microphone circuit during power-up. Probably the same solution or perhaps isolation. Is there feedback when the mic is held close to the speaker during receive? That would indicate a poor PTT connection. See if the switch is flaky. john AD5YE
manojkg VU3YUH All Messages By This Member #21044 Please use 8 ohm speaker..... manoj
Sourav #21050 开云体育 8ohms doesn’t solve the issue !! ? -Vu3Cgb ? toggle quoted message Show quoted text From: [email protected] [mailto:[email protected]] On Behalf Of manojkg VU3YUH Sent: 29 January 2017 08:15 PM To: [email protected] Subject: Re: [BITX20] Shrill noise on power up !! ? Please use 8 ohm speaker..... manoj
Sandeep Lohia All Messages By This Member #21089 'Repair & Reuse or Recycle E-Waste' toggle quoted message Show quoted text On Jan 28, 2017 3:24 PM, "Sourav" <sourav.relja@...> wrote: > > I get a “sharp shrilling tone” while the Bitx’s vol.on/off switch is toggled on ?!!….just beginning part about 2mm after which its normal > > sweep of the Rx volume up/dwn. How to stop it. > use wire wound... > …though the radio’s working fine & am getting a 9-10w o/p > > ? > > 73s, > > vu3cgb > > ? >
SV1RHL All Messages By This Member #21103 Same issue here ... ?I also use 8ohms speaker. ? ? Any other ideas?
Sourav #21149 Solved it by interchanging the 10k pots brown & red wires...!! Wrks fine now...i hv started making contacts already...though the vfo drifting issue is there. Wiring up a digital pll synth vfo now and then latr would try a pushpull PA for getting QRO... 73s, Sourav Vu3Cgb toggle quoted message Show quoted text On Jan 30, 2017 2:30 AM, <chryssot@...> wrote: Same issue here ...? I also use 8ohms speaker. ? ? Any other ideas?

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