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Bitx40 very loud, high-pitched, noise?
#bitx40help
#bitx40
#noise
Bob - I didn't mean feeding 20V straight to the radio, but feeding it to a linear regulator like L7812CV to obtain clean 12V.
Bob - I didn't mean feeding 20V straight to the radio, but feeding it to a linear regulator like L7812CV to obtain clean 12V.
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SP9DEV
· #80930
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Bitx40 very loud, high-pitched, noise?
#bitx40help
#bitx40
#noise
I found a 15V 1A AC supply, that definitely is a simple transformer. If I rectify the output with simple 4-diode ful lwave rectifier, add a capacitance across the output and feed it to something like
I found a 15V 1A AC supply, that definitely is a simple transformer. If I rectify the output with simple 4-diode ful lwave rectifier, add a capacitance across the output and feed it to something like
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By
SP9DEV
· #80911
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Bitx40 very loud, high-pitched, noise?
#bitx40help
#bitx40
#noise
How would you go about beefing up a cheap supply?
How would you go about beefing up a cheap supply?
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By
SP9DEV
· #80900
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Bitx40 very loud, high-pitched, noise?
#bitx40help
#bitx40
#noise
Hi! I've just came back to trying to get my Bitx40 to work, and when I turn on the radio, I hear a terribly loud noise (link to listen below). The radio works fine, because I can hear some operators b
Hi! I've just came back to trying to get my Bitx40 to work, and when I turn on the radio, I hear a terribly loud noise (link to listen below). The radio works fine, because I can hear some operators b
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By
SP9DEV
· #80894
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Bitx40 very loud, high-pitched, low frequency noise
Alright, time for a follow-up: I've added two 47nF (0.094uF total) ceramic caps, one 330pF ceramic cap, one 10uF electrolytic cap and another one 100uF cap across the DC input. Unfortunately, the prob
Alright, time for a follow-up: I've added two 47nF (0.094uF total) ceramic caps, one 330pF ceramic cap, one 10uF electrolytic cap and another one 100uF cap across the DC input. Unfortunately, the prob
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By
SP9DEV
· #71344
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Bitx40 very loud, high-pitched, low frequency noise
Thank you so much for your help Woody! I'll try to get my hand on a small ceramic cap and let you know if this resolved the problem. I'll also try to salvage the ferrite sleeve from an old cable. I'll
Thank you so much for your help Woody! I'll try to get my hand on a small ceramic cap and let you know if this resolved the problem. I'll also try to salvage the ferrite sleeve from an old cable. I'll
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By
SP9DEV
· #71324
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Bitx40 very loud, high-pitched, low frequency noise
Thanks Woody :D Would adding a very small capacitor (nano/pico order) help as well? Or would this be too small to make any difference? And another question, does anyone know any MacGyver way to make s
Thanks Woody :D Would adding a very small capacitor (nano/pico order) help as well? Or would this be too small to make any difference? And another question, does anyone know any MacGyver way to make s
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By
SP9DEV
· #71308
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Bitx40 very loud, high-pitched, low frequency noise
I have some 100uf 50V on hand, added one across bitx40 dc socket, unfortunately the problem persists. I don't have any small caps right now, tomorrow I'll add a small cap and let you guys know if this
I have some 100uf 50V on hand, added one across bitx40 dc socket, unfortunately the problem persists. I don't have any small caps right now, tomorrow I'll add a small cap and let you guys know if this
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By
SP9DEV
· #71306
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Bitx40 very loud, high-pitched, low frequency noise
Alright, I'll try with a 1000uF capacitor, first I'll measure the output voltage with the capacitor between + and gnd lines of the supply output, then I'll give it a try with my bitx by soldering the
Alright, I'll try with a 1000uF capacitor, first I'll measure the output voltage with the capacitor between + and gnd lines of the supply output, then I'll give it a try with my bitx by soldering the
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By
SP9DEV
· #71303
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Bitx40 very loud, high-pitched, low frequency noise
Wait a second, wouldn't soldering a large cap on a switched power supply create an overvoltage? As far as I remember, switch-mode supply units create low voltage by switching higher voltage on and off
Wait a second, wouldn't soldering a large cap on a switched power supply create an overvoltage? As far as I remember, switch-mode supply units create low voltage by switching higher voltage on and off
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By
SP9DEV
· #71300
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Bitx40 very loud, high-pitched, low frequency noise
I'll try to solder some caps to the power socket in bitx, some large ones nd some small ones for fast response. Maybe this will help.
I'll try to solder some caps to the power socket in bitx, some large ones nd some small ones for fast response. Maybe this will help.
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By
SP9DEV
· #71298
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Bitx40 very loud, high-pitched, low frequency noise
Found 3 other pairs of headphones (nokia, motorola and some no-name headphones), the problem persists. However, I also found another wall-plug power supply, this one with a ferrite choke and rated 12V
Found 3 other pairs of headphones (nokia, motorola and some no-name headphones), the problem persists. However, I also found another wall-plug power supply, this one with a ferrite choke and rated 12V
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By
SP9DEV
· #71242
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Bitx40 very loud, high-pitched, low frequency noise
I'm running the whole kit at 12V 3A from a wall-plug type of supply. The headphones are 23ohm apple headphones. Where would I exactly solder the 10ohm and 0.1uf?
I'm running the whole kit at 12V 3A from a wall-plug type of supply. The headphones are 23ohm apple headphones. Where would I exactly solder the 10ohm and 0.1uf?
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By
SP9DEV
· #71236
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Bitx40 very loud, high-pitched, low frequency noise
@Raj vu2zap The problem is at any volume
@Raj vu2zap The problem is at any volume
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By
SP9DEV
· #71219
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Bitx40 very loud, high-pitched, low frequency noise
@Ian Reeve the problem remains.
@Ian Reeve the problem remains.
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By
SP9DEV
· #71218
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Bitx40 very loud, high-pitched, low frequency noise
I tried unplugging the volume control completely, the problem persists
I tried unplugging the volume control completely, the problem persists
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By
SP9DEV
· #71213
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Bitx40 very loud, high-pitched, low frequency noise
Please help
By
SP9DEV
· #71211
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Bitx40 very loud, high-pitched, low frequency noise
Fun fact, when I start to touch and move around the brown wire from volume control knob, I can hear local FM radio station.
Fun fact, when I start to touch and move around the brown wire from volume control knob, I can hear local FM radio station.
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By
SP9DEV
· #71200
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Bitx40 very loud, high-pitched, low frequency noise
Hi! I've just finished assembling my Bitx40, and when I turn on the radio, I hear a terribly loud noise (link to listen below). The radio works fine, because I can hear some operators behind that nois
Hi! I've just finished assembling my Bitx40, and when I turn on the radio, I hear a terribly loud noise (link to listen below). The radio works fine, because I can hear some operators behind that nois
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By
SP9DEV
· #71198
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