str8tlk
Active Member
will testing the remaining transistors on the board with them connected affect the readings? I have brand new main output can transistors and insulators.
Onkyo Tx-8500 Trouble
- Thread starter str8tlk
- Start date
will testing the remaining transistors on the board with them connected affect the readings? I have brand new main output can transistors and insulators.
str8tlk
Active Member
goat67
Addicted Member
Until you get a schematic available lets not worry about testing. Link you posted does not allow down load
The subs I recommended will not work pinouts are wrong....
Last edited:
Jon_Logan
Addicted Member
The manual link worked for me. ... in the Bloomberg ad box.
Okay, Q-8/Q-9 had to be subbed from the 2SC1628 and 2SA818 which are
TO-202 case styles (E-B-C) to 2SC4793 and 2SA1837 with have a B-C-E pinout. These are the pre-drivers. I think the subs that you have have insulated packages. Is that correct? If so, you don't need to worry about insulating those.
Make sure your pre-drivers need to be replaced. If they do, you can mount the pre driver subs upside-down on the heatsink, then attach wires to the legs and map them to the correct holes. This is what you do when the pinout is different. .....or you can hunt for the same case style as the originals. Motorola/On-semi MPSU06 comes to mind. Anyway, you do have the option to use the subs that you got.
For the drivers: Q-10/Q-11 Originally 2SC1669 (Q-10) and 2SA839(Q-11). If you need to sub those, the 2SC2238 and 2SA968 look pretty good. You can get the 'B' suffix which have a higher voltage rating, but I don't think you need it.
With the pre-drivers and drivers installed, leave the outputs out for the time being. Do not connect a load yet. Turn on the set and measure DC volts between ground and the 'SP' terminal on the pwer amp board. If that is ~0 (50mV or less), go to the next step. The next step is measure DC volts between 'B1' and 'B2' on the power amp board. This should be around 1.2 volts. If it is, you can put the output transistors in and check/adjust bias.
I don't know where exactly this is left off, but this is kind of a general overview of what I'd do as I understand the state of things.
Okay, Q-8/Q-9 had to be subbed from the 2SC1628 and 2SA818 which are
TO-202 case styles (E-B-C) to 2SC4793 and 2SA1837 with have a B-C-E pinout. These are the pre-drivers. I think the subs that you have have insulated packages. Is that correct? If so, you don't need to worry about insulating those.
Make sure your pre-drivers need to be replaced. If they do, you can mount the pre driver subs upside-down on the heatsink, then attach wires to the legs and map them to the correct holes. This is what you do when the pinout is different. .....or you can hunt for the same case style as the originals. Motorola/On-semi MPSU06 comes to mind. Anyway, you do have the option to use the subs that you got.
For the drivers: Q-10/Q-11 Originally 2SC1669 (Q-10) and 2SA839(Q-11). If you need to sub those, the 2SC2238 and 2SA968 look pretty good. You can get the 'B' suffix which have a higher voltage rating, but I don't think you need it.
With the pre-drivers and drivers installed, leave the outputs out for the time being. Do not connect a load yet. Turn on the set and measure DC volts between ground and the 'SP' terminal on the pwer amp board. If that is ~0 (50mV or less), go to the next step. The next step is measure DC volts between 'B1' and 'B2' on the power amp board. This should be around 1.2 volts. If it is, you can put the output transistors in and check/adjust bias.
I don't know where exactly this is left off, but this is kind of a general overview of what I'd do as I understand the state of things.
str8tlk
Active Member
Good news! I found the original, Q10 Q11 Transistors. Just gotta check them now. Tested them. Both are GOOD!
I have R39~R42 four: 0.47 ohm 5w cement resistors on hand.
Resistors
R29, R30 two (2): 47 ohm 1w metal oxide film. "The one that fried in the beginning"
R33~R36 six (6): 2.7 ohm 1w Metal.
--------------------------------------------
Transistors Q08,Q09
(Q08)
Toshiba Japanese Transistor 2SC1628(O) - Available substitute: Toshiba 2SC4793 (F,M)
Si NPN Power HF BJT
V(BR)CEO (V)=150
V(BR)CBO (V)=180
I(C) Abs.(A) Collector Current=50m
Absolute Max. Power Diss. (W)=1.0
I(CBO) Max. (A)=1.0u
h(FE) Min. Static Current Gain=70
h(FE) Max. Current gain.=240
@I(C) (A) (Test Condition)=10m
@V(CE) (V) (Test Condition)=5.0
f(T) Min. (Hz) Transition Freq=120M
Status=Discontinued
Package=TO-202var
Military=N
(Q09)
Toshiba Japanese Transistor 2SA818(O) - Available substitute: Toshiba 2SA1837 (F,M)
Si PNP Power BJT
V(BR)CEO (V)=150
V(BR)CBO (V)=180
I(C) Abs.(A) Collector Current=50m
Absolute Max. Power Diss. (W)=1.0
I(CBO) Max. (A)=1.0u
h(FE) Min. Static Current Gain=70
h(FE) Max. Current gain.=240
@I(C) (A) (Test Condition)=10m
@V(CE) (V) (Test Condition)=5.0
f(T) Min. (Hz) Transition Freq=120M
Status=Discontinued
side note: The two main caps would sweet if Replacements could be found. 10,000 uhf 63v
Thats it folks,
That should get her back on her feet.:thmbsp: well still testing to be done but this would complete the PA board. Any one up for getiing me a work order from a good source with quality components?
I have R39~R42 four: 0.47 ohm 5w cement resistors on hand.
Resistors
R29, R30 two (2): 47 ohm 1w metal oxide film. "The one that fried in the beginning"
R33~R36 six (6): 2.7 ohm 1w Metal.
--------------------------------------------
Transistors Q08,Q09
(Q08)
Toshiba Japanese Transistor 2SC1628(O) - Available substitute: Toshiba 2SC4793 (F,M)
Si NPN Power HF BJT
V(BR)CEO (V)=150
V(BR)CBO (V)=180
I(C) Abs.(A) Collector Current=50m
Absolute Max. Power Diss. (W)=1.0
I(CBO) Max. (A)=1.0u
h(FE) Min. Static Current Gain=70
h(FE) Max. Current gain.=240
@I(C) (A) (Test Condition)=10m
@V(CE) (V) (Test Condition)=5.0
f(T) Min. (Hz) Transition Freq=120M
Status=Discontinued
Package=TO-202var
Military=N
(Q09)
Toshiba Japanese Transistor 2SA818(O) - Available substitute: Toshiba 2SA1837 (F,M)
Si PNP Power BJT
V(BR)CEO (V)=150
V(BR)CBO (V)=180
I(C) Abs.(A) Collector Current=50m
Absolute Max. Power Diss. (W)=1.0
I(CBO) Max. (A)=1.0u
h(FE) Min. Static Current Gain=70
h(FE) Max. Current gain.=240
@I(C) (A) (Test Condition)=10m
@V(CE) (V) (Test Condition)=5.0
f(T) Min. (Hz) Transition Freq=120M
Status=Discontinued
side note: The two main caps would sweet if Replacements could be found. 10,000 uhf 63v
Thats it folks,
That should get her back on her feet.:thmbsp: well still testing to be done but this would complete the PA board. Any one up for getiing me a work order from a good source with quality components?
Last edited:
str8tlk
Active Member
So Jon Logan
these are ok to go with?
(Q8) http://www.mouser.com/ProductDetail/Toshiba/2SC4793FM/?qs=sGAEpiMZZMutXGli8Ay4kJeXGdkortY%252bObQMbf2p4DY=
(Q9) http://www.mouser.com/ProductDetail/Toshiba/2SA1837FM/?qs=sGAEpiMZZMutXGli8Ay4kJeXGdkortY%252btxjRUDateDE=
Thanks,
-St8tlk
these are ok to go with?
(Q8) http://www.mouser.com/ProductDetail/Toshiba/2SC4793FM/?qs=sGAEpiMZZMutXGli8Ay4kJeXGdkortY%252bObQMbf2p4DY=
(Q9) http://www.mouser.com/ProductDetail/Toshiba/2SA1837FM/?qs=sGAEpiMZZMutXGli8Ay4kJeXGdkortY%252btxjRUDateDE=
Thanks,
-St8tlk
str8tlk
Active Member
All parts ordered here rarin to heat up.Dim bulb tester built Ready to proceed... Rodger..come in? you there good buddy? out. 
Any one know what type of cap this is. If I were to guess, its some sort of duel staged farad cap or a market ploy to state that two main filter caps are used. Its one of the biggest caps Ive run across in solid states. There Both in great shape and wont be replacing them. Maybe adding a stacked polly but thats about it.
Any one know what type of cap this is. If I were to guess, its some sort of duel staged farad cap or a market ploy to state that two main filter caps are used. Its one of the biggest caps Ive run across in solid states. There Both in great shape and wont be replacing them. Maybe adding a stacked polly but thats about it.
str8tlk
Active Member
Hi Jon,
Im ready to rock & roll. Right on about those caps. Parts are in :yes:, finally digi.
Ive got a stupid question for you. What’s this particular board called? Before I bought it; the other one, "opposite" side had the main output transistors replaced and THATS IT! This one that you’re tackling had the originals. I have new matching pairs now for it made in good old Mexico. just like the other side.
Every one like Pics right :
Ive gotta clean up those solder points..
The left other side:
Im ready to rock & roll. Right on about those caps. Parts are in :yes:, finally digi.
Ive got a stupid question for you. What’s this particular board called? Before I bought it; the other one, "opposite" side had the main output transistors replaced and THATS IT! This one that you’re tackling had the originals. I have new matching pairs now for it made in good old Mexico. just like the other side.
Every one like Pics right :
Ive gotta clean up those solder points..
The left other side:
Last edited:
Jon_Logan
Addicted Member
What is the board (PCB) called?? I give up, what is it called?
Seriously though, It's better if you just give it a name, unless you need to reference the board the the schematic. On the schematic, they (Onkyo) probably ID with a number (such as D-3826) or a description (such as "amp board", "output PCB", "Main PCB", etc.). It looks like Onkyo calls it
"NADA-405".
I know you've already put the outputs back in and it'll be a mess to pull them with their fresh coat of heatsink compound, but please consider that they are easy to remove and that things go bad in a hurry if anything is wrong in front of the outputs. I'm not trying to scare you. I'm just saying that you could take another step to try to avoid expensive damage should anything be wrong.
You have a dim bulb tester at your disposal? If yes, use that. You have a VariAc? If yes, use that.
So here's a choice I'd recommend.
Choice 1: Disconnect the loads (8 ohm or speaker), remove the outputs VariAc slowly while measuring the voltage across B1 and B2 (the lines the feed the output bases). You should get ~ 1.1~1.2 V(DC) across there. Measure from "SP" to chassis and confirm ~0 V(DC) +/-50mV is okay. If that pans out, reinstall the outputs (in their right places) and fire it up with the Dim bulb tester in line. Measure across one of the emmiter resistors. If close to spec, plug directly into the outlet (no more dim bulb), let it warm up about 20 mins and perform a bias adjustment.
Choice 2: Leave the outputs in place. Turn up the VariAc slowly to about 30VAC. Measure DC volts across all of the emmiter resistors. R's 39~42 (0.47/5W). You should see 0~20mV(DC). If you see higher than that, bring the VariAc down some. Try to adjust the bias control (R-522) to lower the voltage seen across the emmiter resistor. If the bias control has no effect, Stop there and report that. If the voltage across the emmiter resistor is okay, raise the VariAc voltage while looking at the various emmiter resistor readings. If those look okay at full line voltage, measure the DC Volts from "SP" to chassis or ground. It should be 50mV or less.
I can't stress this enough, be very carefull when placing probes on test points. Try not to be too nervous. Nervousness makes bad stuff happen. If you feel squeamish about getting a probe onto a hard to reach spot, just turn down the VariAc, wait for a second (for stuff to discharge), place the probe, VariAc back up. No harm, no foul. I can't tell you how many things I've seen need to be paired due to slipped probes. It happens too fast.
The Manual say's "Adjust for 40 + 10mV". so is that 50mV??? :scratch2: I don't know about that. That sounds high to me. I'd look for about 19mV measured from "ID" and "CT" terminals. This will be about 40mA per output device and if the rail voltage is about 60V, the transistors will dissipate about 2.5W each
Seriously though, It's better if you just give it a name, unless you need to reference the board the the schematic. On the schematic, they (Onkyo) probably ID with a number (such as D-3826) or a description (such as "amp board", "output PCB", "Main PCB", etc.). It looks like Onkyo calls it
"NADA-405".
I know you've already put the outputs back in and it'll be a mess to pull them with their fresh coat of heatsink compound, but please consider that they are easy to remove and that things go bad in a hurry if anything is wrong in front of the outputs. I'm not trying to scare you. I'm just saying that you could take another step to try to avoid expensive damage should anything be wrong.
You have a dim bulb tester at your disposal? If yes, use that. You have a VariAc? If yes, use that.
So here's a choice I'd recommend.
Choice 1: Disconnect the loads (8 ohm or speaker), remove the outputs VariAc slowly while measuring the voltage across B1 and B2 (the lines the feed the output bases). You should get ~ 1.1~1.2 V(DC) across there. Measure from "SP" to chassis and confirm ~0 V(DC) +/-50mV is okay. If that pans out, reinstall the outputs (in their right places) and fire it up with the Dim bulb tester in line. Measure across one of the emmiter resistors. If close to spec, plug directly into the outlet (no more dim bulb), let it warm up about 20 mins and perform a bias adjustment.
Choice 2: Leave the outputs in place. Turn up the VariAc slowly to about 30VAC. Measure DC volts across all of the emmiter resistors. R's 39~42 (0.47/5W). You should see 0~20mV(DC). If you see higher than that, bring the VariAc down some. Try to adjust the bias control (R-522) to lower the voltage seen across the emmiter resistor. If the bias control has no effect, Stop there and report that. If the voltage across the emmiter resistor is okay, raise the VariAc voltage while looking at the various emmiter resistor readings. If those look okay at full line voltage, measure the DC Volts from "SP" to chassis or ground. It should be 50mV or less.
I can't stress this enough, be very carefull when placing probes on test points. Try not to be too nervous. Nervousness makes bad stuff happen. If you feel squeamish about getting a probe onto a hard to reach spot, just turn down the VariAc, wait for a second (for stuff to discharge), place the probe, VariAc back up. No harm, no foul. I can't tell you how many things I've seen need to be paired due to slipped probes. It happens too fast.
The Manual say's "Adjust for 40 + 10mV". so is that 50mV??? :scratch2: I don't know about that. That sounds high to me. I'd look for about 19mV measured from "ID" and "CT" terminals. This will be about 40mA per output device and if the rail voltage is about 60V, the transistors will dissipate about 2.5W each
str8tlk
Active Member
I didnt put them back in. That picture is the matching left side "amp board"
QUOTE: when I bought it; the other board, "opposite" side had the main output transistors replaced and That was it. This board that you’re tackling has the originals. I have new matching pairs now for it made in good ol Mexico. just like the other side. QUOTE:".
Thank you for clarifying that is an amp board. I was just trying to get an understanding on what the function of the board im working on, Im trying to learn a little here but...soory I wont ask any more questions. Like a power supply regulator board and so on and so on. Which I now have a full under standing from a previous project.
I havnt put any parts in. I have the parts box right in front of me and a pic above of what the board looks like right now. I explained that i need to clean some solder from removing the faulty parts.
I wasnt gonna touch a thing with out your say so...just trying to explain where its at now, thats all.. in my previous post I stated that the rest of the pictures were from the left side of the receiver, the side were not working on. Which I thought would be helpful since those amp boards are identical and that amp board was worked on before I purchased my $400 paper weight.
QUOTE: when I bought it; the other board, "opposite" side had the main output transistors replaced and That was it. This board that you’re tackling has the originals. I have new matching pairs now for it made in good ol Mexico. just like the other side. QUOTE:".
Thank you for clarifying that is an amp board. I was just trying to get an understanding on what the function of the board im working on, Im trying to learn a little here but...soory I wont ask any more questions. Like a power supply regulator board and so on and so on. Which I now have a full under standing from a previous project.
I havnt put any parts in. I have the parts box right in front of me and a pic above of what the board looks like right now. I explained that i need to clean some solder from removing the faulty parts.
I wasnt gonna touch a thing with out your say so...just trying to explain where its at now, thats all.. in my previous post I stated that the rest of the pictures were from the left side of the receiver, the side were not working on. Which I thought would be helpful since those amp boards are identical and that amp board was worked on before I purchased my $400 paper weight.
Last edited:
goat67
Addicted Member
Hello
After reading this thread again here is what you need to do.
Install the resistors that you found to be bad.
Check the original Q10 and Q11 transistors these are good you said
If indeed good install them.
Did you buy the recommended replacements for these?
If you did I would be tempted to install the new ones instead.
Q8 and Q9 here you have to be creative installing the replacements the originals are EBC pin layout
and the new ones are BCE so you need to figure out how to get these installed.
Post pictures after you have finished these steps.
Jon wants you to have the output transistors removed for the first test
I am pretty sure this is the case as the picture shows in a previous post.
If you do not have a Variac then use your DBT for the first turn on but you are not ready for this yet.
Look at these data sheets
http://www.toshiba.com/taec/components2/Datasheet_Sync//66/7846.pdf
http://pdf1.alldatasheet.com/datasheet-pdf/view/168236/TOSHIBA/2SC1628-O.html
After reading this thread again here is what you need to do.
Install the resistors that you found to be bad.
Check the original Q10 and Q11 transistors these are good you said
If indeed good install them.
Did you buy the recommended replacements for these?
If you did I would be tempted to install the new ones instead.
Q8 and Q9 here you have to be creative installing the replacements the originals are EBC pin layout
and the new ones are BCE so you need to figure out how to get these installed.
Post pictures after you have finished these steps.
Jon wants you to have the output transistors removed for the first test
I am pretty sure this is the case as the picture shows in a previous post.
If you do not have a Variac then use your DBT for the first turn on but you are not ready for this yet.
Look at these data sheets
http://www.toshiba.com/taec/components2/Datasheet_Sync//66/7846.pdf
http://pdf1.alldatasheet.com/datasheet-pdf/view/168236/TOSHIBA/2SC1628-O.html
Jon_Logan
Addicted Member
Leave all transistors that are being replaced out? when measuring Jon L.? Q08 Q09 Q10 Q11 plus the main outputs. Im lost...
Yes, leave installed or install Q's 8~11. These are pre-drivers and drivers.
Leave Q's 12~15 (output transistors) out for now. I had thought that the picture with the output transistors installed was from the channel being repaired. Those are not the originals, but probably good subs.
Goat67 has the correct understanding of the approach I am indicating. (Thanks Goat)
I/we can give more specific information if I/we know exactly what test equipment you have at your disposal.
Do you have a Dim Bulb Tester? ... with a 100~200W incandescent bulb installed?
Do you have a VariAc.
If you do or don't have these items, it's okay. It's just easier to give you specific steps when I/we can visualise the equipment you have at your disposal and how to make best use of it.
This amp is generally very simple and straightforward. With the work that you've done before, you are very close to completion.
str8tlk
Active Member
Thanks guys,
Yes Q9 is a TO-220 PNP. Can I just filp it around? These new ones are not metal backed like the originals btw.
Q8 has the same TO-220 NPN ebc pin layout as original. I dont have a variac I have a dim bulb tester with a 13w florescent and a 200w incandescent on hand. I can always pick up some different wattage bulbs though. Stock up on some incandescents before there out lawed in my state next year.
Yes Q9 is a TO-220 PNP. Can I just filp it around? These new ones are not metal backed like the originals btw.
Q8 has the same TO-220 NPN ebc pin layout as original. I dont have a variac I have a dim bulb tester with a 13w florescent and a 200w incandescent on hand. I can always pick up some different wattage bulbs though. Stock up on some incandescents before there out lawed in my state next year.
Last edited:
goat67
Addicted Member
What are the part numbers for the replacements I give you the links to the data sheets and if you are using what you said the pin outs are different.
I do have concerns with the heat sink mounting of these transistors
Did these transistors have a mica insulators?
I do not think so I think they used the heat sink to have the collectors of Q8 and Q10 same with Q9 and Q11 common forming a darlington configuration.
str8tlk
Active Member
The new ones look likw this no metal back
_sml.jpg)
---------------------------------------------
Q08 : Toshiba 2SC4793 (F,M) TO-220 NPN
TRANS NPN 230V 1A 2-10R1A - 2SC4793 - Discrete Semiconductor Products
Digi-Key Part Number 2SC4793-ND
Manufacturer Part Number 2SC4793
Description TRANS NPN 230V 1A 2-10R1A
Purchase Transistor (bjt) - Single Discrete Semiconductor Product 1A 230V 2W Toshiba NPN 2SC4793
Quantity Item Number Customer Reference
Specifications for Transistor (bjt) - Single Discrete Semiconductor Product 1A 230V 2W Toshiba NPN 2SC4793
Vendor Toshiba
Category Discrete Semiconductor Products
Transistor Type NPN
Voltage - Collector Emitter Breakdown (Max) 230V
Current - Collector (Ic) (Max) 1A
Power - Max 2W
DC Current Gain (hFE) (Min) @ Ic, Vce 100 @ 100mA, 5V
Vce Saturation (Max) @ Ib, Ic 1.5V @ 50mA, 500mA
Frequency - Transition 100MHz
Current - Collector Cutoff (Max) -
Mounting Type Through Hole
Package / Case 2-10R1A (TO-220 NIS)
Packaging Tube
Lead Free Status Contains Lead
RoHS Status RoHS Non-Compliant
Other Names 2SC4793
2SC4793
----------------------------------------------
Q09: Toshiba 2SA1837 (F,M) TO-220 PNP
Digi-Key Part Number 2SA1837FM-ND
Manufacturer Toshiba
Manufacturer Part Number 2SA1837(F,M)
Description TRANS PNP -230V -1A 2-10R1A
Lead Free Status / RoHS Status Lead free / RoHS Compliant
2SA1837(F,M)
Datasheets 2SA1837
Product Photos 2SA1837(F,M)
Catalog Drawings Bipolar TO-220(NIS) Pin Out
Standard Package 50
Category Discrete Semiconductor Products
Family Transistors (BJT) - Single
Series -
Transistor Type PNP
Current - Collector (Ic) (Max) 1A
Voltage - Collector Emitter Breakdown (Max) 230V
Vce Saturation (Max) @ Ib, Ic 1.5V @ 50mA, 500mA
Current - Collector Cutoff (Max) -
DC Current Gain (hFE) (Min) @ Ic, Vce 100 @ 100mA, 5V
Power - Max 2W
Frequency - Transition 70MHz
Mounting Type Through Hole
Package / Case 2-10R1A (TO-220 NIS)
Packaging Tube
Supplier Device Package TO-220NIS
Catalog Page 1441 (US2011 Interactive)
1441 (US2011 PDF)
Other Names 2SA1837FM
---------------------------------------------------------
Your correct they didnt have mica insulators or thermal interface material.
I have a question... When the metal tab or back is in the rear the pin lay out goes from left to right correct?c:tresbon:
like this :
So the Q08 PNP transistor would have to be flipped around on on the board for the pin lay out to match up correct? Im learning alot here about transistors quick. I suppose I could use some T.I.M on them with a little pin drop of super glue on the corners to hold them to the heat sink, if they put off a lot heat. Ive seen this done on computer component's with great results.
---------------------------------------------
Q08 : Toshiba 2SC4793 (F,M) TO-220 NPN
TRANS NPN 230V 1A 2-10R1A - 2SC4793 - Discrete Semiconductor Products
Digi-Key Part Number 2SC4793-ND
Manufacturer Part Number 2SC4793
Description TRANS NPN 230V 1A 2-10R1A
Purchase Transistor (bjt) - Single Discrete Semiconductor Product 1A 230V 2W Toshiba NPN 2SC4793
Quantity Item Number Customer Reference
Specifications for Transistor (bjt) - Single Discrete Semiconductor Product 1A 230V 2W Toshiba NPN 2SC4793
Vendor Toshiba
Category Discrete Semiconductor Products
Transistor Type NPN
Voltage - Collector Emitter Breakdown (Max) 230V
Current - Collector (Ic) (Max) 1A
Power - Max 2W
DC Current Gain (hFE) (Min) @ Ic, Vce 100 @ 100mA, 5V
Vce Saturation (Max) @ Ib, Ic 1.5V @ 50mA, 500mA
Frequency - Transition 100MHz
Current - Collector Cutoff (Max) -
Mounting Type Through Hole
Package / Case 2-10R1A (TO-220 NIS)
Packaging Tube
Lead Free Status Contains Lead
RoHS Status RoHS Non-Compliant
Other Names 2SC4793
2SC4793
----------------------------------------------
Q09: Toshiba 2SA1837 (F,M) TO-220 PNP
Digi-Key Part Number 2SA1837FM-ND
Manufacturer Toshiba
Manufacturer Part Number 2SA1837(F,M)
Description TRANS PNP -230V -1A 2-10R1A
Lead Free Status / RoHS Status Lead free / RoHS Compliant
2SA1837(F,M)
Datasheets 2SA1837
Product Photos 2SA1837(F,M)
Catalog Drawings Bipolar TO-220(NIS) Pin Out
Standard Package 50
Category Discrete Semiconductor Products
Family Transistors (BJT) - Single
Series -
Transistor Type PNP
Current - Collector (Ic) (Max) 1A
Voltage - Collector Emitter Breakdown (Max) 230V
Vce Saturation (Max) @ Ib, Ic 1.5V @ 50mA, 500mA
Current - Collector Cutoff (Max) -
DC Current Gain (hFE) (Min) @ Ic, Vce 100 @ 100mA, 5V
Power - Max 2W
Frequency - Transition 70MHz
Mounting Type Through Hole
Package / Case 2-10R1A (TO-220 NIS)
Packaging Tube
Supplier Device Package TO-220NIS
Catalog Page 1441 (US2011 Interactive)
1441 (US2011 PDF)
Other Names 2SA1837FM
---------------------------------------------------------
Your correct they didnt have mica insulators or thermal interface material.
I have a question... When the metal tab or back is in the rear the pin lay out goes from left to right correct?c:tresbon:
like this :
So the Q08 PNP transistor would have to be flipped around on on the board for the pin lay out to match up correct? Im learning alot here about transistors quick. I suppose I could use some T.I.M on them with a little pin drop of super glue on the corners to hold them to the heat sink, if they put off a lot heat. Ive seen this done on computer component's with great results.
Last edited: