Uploaded May 2026 | Updated September 2026, 1 hour ago
This is the FP10000Q 10KW Amplifier that has been given me trouble. It appears to have a problem with the Idle Current / Bias Circuit. Sometimes you need to understand how something should work before you can figure out why it isn't working. Here is a slightly deep dive into the bias circuit with no complicated maths, just real life diagnostic work. If you ever wondered how this circuit works then give this video a go.
Previously on LER
youtube.com/watch?v=ztdPtT73dk4
youtube.com/watch?v=_HBGh2izzaM
youtube.com/watch?v=CoImjSYt0Lg
youtube.com/watch?v=FmT7KwkOloA
Discount Codes
WORLDWIDE until 1st October
👉Click https://s.click.aliexpress.com/e/_EJTSFLU or enter the search code [AY0QDR] on the AliExpress homepage or enjoy extra savings with the exclusive discount codes below.
🌟 Remember, these codes can be used on almost all items AliExpress.
$3 off on orders over $29:【IFP4Z7CD】
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USA ONLY until 1st October
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$3 off on orders over $22: 【IFPJJA2V】
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For All Your PCB needs: free $5 discount coupon
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Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission.
DM40C
https://s.click.aliexpress.com/e/_c4q1dFy7
Aneng AN870 (Same as Zoyi ZT219)
https://s.click.aliexpress.com/e/_c2wcOv9N
Zoyi ZT-DQ02
https://s.click.aliexpress.com/e/_oB2u3sT
WinAPEX 268B Clamp Meter
https://s.click.aliexpress.com/e/_opJTjEP
VC480C+ MILLIOHM METER
https://s.click.aliexpress.com/e/_onE0FaJ
MESR-100 ESR METER
https://s.click.aliexpress.com/e/_oombcej
XC6013L CAPACITOR METER
https://s.click.aliexpress.com/e/_omnOxub
FNB58 USB ANALYZER
https://s.click.aliexpress.com/e/_c3hysTXt
4KV Breakdown Tester
https://s.click.aliexpress.com/e/_omKXmND
LED Backlight Tester
https://s.click.aliexpress.com/e/_oCRPzdl
NI-210SC Curve Tracer
https://s.click.aliexpress.com/e/_o2e0Par
NI210SJ (cheaper option but watch my review)
https://s.click.aliexpress.com/e/_oD60O0D
PCI POST ANALYZER
https://s.click.aliexpress.com/e/_c44XQKaj
FNIRSI 1014D SCOPE
https://s.click.aliexpress.com/e/_c2xAnnbv
NPS3010W 30V 10A PSU
https://s.click.aliexpress.com/e/_oDuHLdl
Nice-Power Dual 120V 3A PSU
https://s.click.aliexpress.com/e/_okGvYQ7
HR1520 Pro Short Killer
https://s.click.aliexpress.com/e/_c2RE3ToB
KSGER T12 Soldering Station
https://s.click.aliexpress.com/e/_omqBjWR
AIFEN-A9 PRO Soldering Station C115/C210/C245/C470
https://s.click.aliexpress.com/e/_ongFBEJ
C470 Soldering Iron & Tips
https://s.click.aliexpress.com/e/_opm1OND
https://s.click.aliexpress.com/e/_oDVNACf
QUICK 861DW
https://s.click.aliexpress.com/e/_ooW7QGR
PROS'KIT SS-331H
https://s.click.aliexpress.com/e/_omxB5H5
Sequre HT140 Hot Tweezers
https://s.click.aliexpress.com/e/_opH6KS3
KADA 853B Preheater
https://s.click.aliexpress.com/e/_opPOUgX
FNIRSI SWM-10 Spot Welder
https://s.click.aliexpress.com/e/_ooZey3t
INFIRAY P2 PRO IR CAMERA + MACRO LENS
https://s.click.aliexpress.com/e/_ootcxPv
TOOLTOP ET13S THERMAL CAMERA METER
https://s.click.aliexpress.com/e/_c4MMdodZ
ET13S MACRO LENS
https://s.click.aliexpress.com/e/_ol9d8hh
Trinocular Microscope
https://s.click.aliexpress.com/e/_okJictD
TOMLOV TM4K AF FLEX
https://s.click.aliexpress.com/e/_oBirts7
TL866 II+ PROGRAMMER
https://s.click.aliexpress.com/e/_c32XDS1D
NC-559-ASM FLUX
https://s.click.aliexpress.com/e/_onMlHRD
DESOLDER BRAID (I use size 8045)
https://s.click.aliexpress.com/e/_onhlLkx
HX-T100 SOLDER
https://s.click.aliexpress.com/e/_o2DHwJH
ESD-11 TWEEZERS
https://s.click.aliexpress.com/e/_om2F4w3
Learn Electronics Repair Discord
discord.gg/vam6YC8vwU
If you would like to support this channel
You can send donations
paypal.com/paypalme/youtubeLER
You can subscribe to Patreon
patreon.com/learnelectronicsrepair
Or you can click JOIN to become a channel member
Thank you
Richard
This is the FP10000Q 10KW Amplifier that has been given me trouble. It appears to have a problem with the Idle Current / Bias Circuit. Sometimes you need to understand how something should work before you can figure out why it isn't working. Here is a slightly deep dive into the bias circuit with no complicated maths, just real life diagnostic work. If you ever wondered how this circuit works then give this video a go.
Previously on LER
youtube.com/watch?v=ztdPtT73dk4
youtube.com/watch?v=_HBGh2izzaM
youtube.com/watch?v=CoImjSYt0Lg
youtube.com/watch?v=FmT7KwkOloA
Discount Codes
WORLDWIDE until 1st October
👉Click https://s.click.aliexpress.com/e/_EJTSFLU or enter the search code [AY0QDR] on the AliExpress homepage or enjoy extra savings with the exclusive discount codes below.
🌟 Remember, these codes can be used on almost all items AliExpress.
$3 off on orders over $29:【IFP4Z7CD】
$6 off on orders over $59:【IFPAJEZM】
$9 off on orders over $89:【IFPRNO4O】
$16 off on orders over $149:【IFPUJ36B】
$23 off on orders over $199:【IFPTOX9W】
$30 off on orders over $269:【IFPZKRLP】
$40 off on orders over $369:【IFP31PZF】
$50 off on orders over $469:【IFPW85ON】
$60 off on orders over $599:【IFPPCTYJ】
$70 off on orders over $699:【IFPNP6MS】
USA ONLY until 1st October
👉Click https://s.click.aliexpress.com/e/_EG4DFJU or enter the search code [AYECF8] on the AliExpress homepage or enjoy extra savings with the exclusive discount codes below.
$3 off on orders over $22: 【IFPJJA2V】
$5 off on orders over $38: 【FPFTKGF】
$8 off on orders over $60: 【IFP1E8XE】
$14 off on orders over $99:【IFPY43E9】
$22 off on orders over $159:【IFPFYLCK】
$33 off on orders over $239:【IFPPF7W3】
$52 off on orders over $359:【IFPCOJYA】
$66 off on orders over $469:【IFPR0LZX】
For All Your PCB needs: free $5 discount coupon
pcbway.com/setinvite.aspx?inviteid=561767
Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission.
DM40C
https://s.click.aliexpress.com/e/_c4q1dFy7
Aneng AN870 (Same as Zoyi ZT219)
https://s.click.aliexpress.com/e/_c2wcOv9N
Zoyi ZT-DQ02
https://s.click.aliexpress.com/e/_oB2u3sT
WinAPEX 268B Clamp Meter
https://s.click.aliexpress.com/e/_opJTjEP
VC480C+ MILLIOHM METER
https://s.click.aliexpress.com/e/_onE0FaJ
MESR-100 ESR METER
https://s.click.aliexpress.com/e/_oombcej
XC6013L CAPACITOR METER
https://s.click.aliexpress.com/e/_omnOxub
FNB58 USB ANALYZER
https://s.click.aliexpress.com/e/_c3hysTXt
4KV Breakdown Tester
https://s.click.aliexpress.com/e/_omKXmND
LED Backlight Tester
https://s.click.aliexpress.com/e/_oCRPzdl
NI-210SC Curve Tracer
https://s.click.aliexpress.com/e/_o2e0Par
NI210SJ (cheaper option but watch my review)
https://s.click.aliexpress.com/e/_oD60O0D
PCI POST ANALYZER
https://s.click.aliexpress.com/e/_c44XQKaj
FNIRSI 1014D SCOPE
https://s.click.aliexpress.com/e/_c2xAnnbv
NPS3010W 30V 10A PSU
https://s.click.aliexpress.com/e/_oDuHLdl
Nice-Power Dual 120V 3A PSU
https://s.click.aliexpress.com/e/_okGvYQ7
HR1520 Pro Short Killer
https://s.click.aliexpress.com/e/_c2RE3ToB
KSGER T12 Soldering Station
https://s.click.aliexpress.com/e/_omqBjWR
AIFEN-A9 PRO Soldering Station C115/C210/C245/C470
https://s.click.aliexpress.com/e/_ongFBEJ
C470 Soldering Iron & Tips
https://s.click.aliexpress.com/e/_opm1OND
https://s.click.aliexpress.com/e/_oDVNACf
QUICK 861DW
https://s.click.aliexpress.com/e/_ooW7QGR
PROS'KIT SS-331H
https://s.click.aliexpress.com/e/_omxB5H5
Sequre HT140 Hot Tweezers
https://s.click.aliexpress.com/e/_opH6KS3
KADA 853B Preheater
https://s.click.aliexpress.com/e/_opPOUgX
FNIRSI SWM-10 Spot Welder
https://s.click.aliexpress.com/e/_ooZey3t
INFIRAY P2 PRO IR CAMERA + MACRO LENS
https://s.click.aliexpress.com/e/_ootcxPv
TOOLTOP ET13S THERMAL CAMERA METER
https://s.click.aliexpress.com/e/_c4MMdodZ
ET13S MACRO LENS
https://s.click.aliexpress.com/e/_ol9d8hh
Trinocular Microscope
https://s.click.aliexpress.com/e/_okJictD
TOMLOV TM4K AF FLEX
https://s.click.aliexpress.com/e/_oBirts7
TL866 II+ PROGRAMMER
https://s.click.aliexpress.com/e/_c32XDS1D
NC-559-ASM FLUX
https://s.click.aliexpress.com/e/_onMlHRD
DESOLDER BRAID (I use size 8045)
https://s.click.aliexpress.com/e/_onhlLkx
HX-T100 SOLDER
https://s.click.aliexpress.com/e/_o2DHwJH
ESD-11 TWEEZERS
https://s.click.aliexpress.com/e/_om2F4w3
Learn Electronics Repair Discord
discord.gg/vam6YC8vwU
If you would like to support this channel
You can send donations
paypal.com/paypalme/youtubeLER
You can subscribe to Patreon
patreon.com/learnelectronicsrepair
Or you can click JOIN to become a channel member
Thank you
Richard
