A few days ago I got a knock at my gate very early in the
morning and I wondered what could have necessitated the visit and I almost came
out armed.
Upon opening the gate I found one of my neighbor standing
there holding a woofer and after excusing himself he told me that he wanted it checked
urgently and he suspect it burnt after the power surge though I can’t remember
experiencing any in my house.
I took the machine and kept it in my workshop which is
within my house and went to work. In the evening I came back and went straight
to the woofer and before opening I could smell something burnt inside and after
opening this is what I saw.
Yes! The four bridge
diodes were burnt beyond recognition.
Before continuing I
decided to check if the transformer was gone or not and after dis-connecting it
from the board I applied the power and I was able to test all the outputs and
were okay and with this I concluded the transformer was okay.
To me this was a big
relief since getting the spare for this kind of transformer is not easy in my
place.
I decided to replace
the four diodes and therefore I removed them carefully and replaced them, since
the two fuses were okay I did not suspect any more components shorted.
I then decided to
apply the power with the motherboard connected but since I was not sure if
there were any other component shorted I decided to use my series lamp current
limiter.
After applying the
power I noted the bulb remained bright and this means there was still something
shorted in the system.
To get the culprit I
decided to use the touch method whereby after applying the power via the series
bulb for a few minutes dis-connected the power and started touching main suspect
component which are prone to shorting like transistors, I.Cs and I after
touching one of the amplifier I.C TDA2030A I noted it was very hot for my
finger and concluded this must be one of the culprit.
Also keen observation
I noted one of its leg was dark meaning it was getting very hot to the point of
changing the color as you can see the picture above.
I pulled it out of
the circuit and again applied the power and this time the series bulb lite and
then went off.
This is a good sign
that no more shorted component in there and therefore got a replacement ic
TDA2030A which was readily available in my store.
I replaced it and
after applying the power I got aloud humming sound from the woofer and I
concluded I may have finally got the system working again.
Here is the inside of
the woofer
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great i like the information.
ReplyDeleteThanks for your feedback Khan.
DeleteRegards Humphrey
Good job Sir,
ReplyDeleteThanks Yogesh
DeleteRegards Humphrey
Dear Sir,
ReplyDeleteThanks for your useful classes, will you please explain me, How to add the USB port option in old CD player.
add MP3 Decoder Board..
DeleteRegards Humphrey
Hello sir . I have the same problems but how did u get the value of those burnt diod??
DeleteThank you
Use normal diodes...rectifier diodes.
DeleteRegards Humphrey
My sayona lost the should. What could be the problem.
ReplyDeletemine too and the power is getting thru
DeleteI would like my radio to be fixed where can I find your shop
ReplyDeleteMy sayona transistors are hot and are meassuring a shot .what may be the ploblem ?
ReplyDeleteMy sayona has just went off from functioning and i am told that the problem is the usb/sd port. Where can i get one thats made from sayona repair accessories
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DeleteGreat tutorial
ReplyDeleteI need a sayonna sht 1148bt motherboard
ReplyDeleteMy saying has aproblem with bass, sometimes there's bass na other time it's on there, any help pls
ReplyDeleteMy Sayona woofer SHT-1134 lost bass and frequently goes off.what could be the culprit?
ReplyDeleteIf your LED has a thick and well-made glass panel then you may have fewer issues with a compromised viewing angle or glare down the road. best smart tv
ReplyDeleteHello, I have a sayona pps SHT-11488T.the is a problem with the bass I have tried repairing by replacing transistor but iam not successful. It was brought to my workshop from another workshop.
ReplyDeleteKindly if you have an idea on how the transistors are placed, assist
Hello, I have a sayona pps SHT-11488T.the is a problem with the bass I have tried repairing by replacing transistor but iam not successful. It was brought to my workshop from another workshop.
ReplyDeleteKindly if you have an idea on how the transistors are placed, assist
Were you successful since got the same issue
DeleteUse 1943 and 5200 transistors for best output. Then check drivers 5551,5401, 2683, 1013 lastly resistors around if they have open replace with same value.
Deletemy sayona pps sht -1132bt 1s not displaying after powering it but i can hear the humming sound
ReplyDeleteCheck rectification replace diodes and also if capacitor have swollen replace also if needed. After there check the regulator 7805 output
DeleteMine having the same problem with two diodes bridge is dark it is not performing well asist me wat to do
ReplyDeleteThat's good
ReplyDeleteI need speaker change for my sayona woofer
ReplyDeleteGreat.wgat other resistor can I use to replace a cerment 5W0.25ohmsJ resistor please.
ReplyDeleteThank you
My sayona SHT-1079BT dead help
ReplyDeletePlease can post the schematic
ReplyDeleteCircuit diagram
Audia menu not working
ReplyDeleteMy woofer does not produce any sound despite of it being on
ReplyDeleteI have a question my sayona 1149bt can't produce bass but tremble is functioning well what might be the problem because it is using tip 41&42 for bass
DeleteCheck the drivers transistor if any short replace .5401,5551,2386 ,1013 replace them. Then check main output transistor. Tip42(pnp) and tip41 (npn) .eqvaulent tip 42,(1941,688,1943)tip 41(d688 ,5198,5200)
DeleteWhat isthe price to the motherbord
ReplyDeleteMy sayona woofer take long time to open after connecting to power what might be the problem......
ReplyDeleteMy sayona woofer take long time to open after connecting to power what might be the problem......
ReplyDeleteI Need to know IC number os Sayona Model SHT. 1203BT
ReplyDeletePrice of IC of Sayona model SHT. 1203BT
ReplyDeleteHow much is mother board of sayona sh11bt
ReplyDeleteI want one piece
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ReplyDeleteI need you contact
ReplyDeleteMy cecuit has buns beyond regognition no where you can replace the two diods do you have an image that can assist if I have to replace it with a rectifier.
ReplyDeleteThank you sir good job dan
ReplyDeleteHallo I have a sayona1206 have a problem with bass please assist
ReplyDeleteMine has no bass, its producing roaring sound.
ReplyDeleteThat's great,i want to use the same model of transformer to a 2.1 amplifier is it possible and how?
ReplyDeleteHow do i use the same transformer to a 2.1 amplifier
ReplyDeleteDiode burnt beyond recognition
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ReplyDeleteMy sayonapps sht-11318T is not turning after connecting to power supply
ReplyDeleteHow can i repar the speker cable
ReplyDeleteDo you have bass speaker 🔊 and it's how much plus the IC of soud
ReplyDelete