Idk why the emitter has a voltage, it's just a resistor and cap connected to ground. Check that out. The pin out should be BCE, left to right, front of transistor. Maybe you read that backwards?
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Another 55v no xmit
- Thread starter Hawkeye351
- Start date
If the resistors are correct, and the input voltage is correct, the base should show 1.5 volts. That's...
Vo=Vi(r2/(r1+r2))
Assuming 8.29 volts x 330/(1500+330)
8.29x330/1830
8.29x.180= 1.4949v
Something is amiss here.
Vo=Vi(r2/(r1+r2))
Assuming 8.29 volts x 330/(1500+330)
8.29x330/1830
8.29x.180= 1.4949v
Something is amiss here.
Oh ok, I'm an idiot...lol...
Base is 1.29v
Collector is 8.29v
Emitter is 0.00v
That's with TR45 removed.
Base is 1.29v
Collector is 8.29v
Emitter is 0.00v
That's with TR45 removed.
Groovy. Find another transistor for that spot and replace it.
Update:
Went ahead and replaced tr45 with a new one.
Now:
Base - 1.51v
Collector - 8.28v
Emitter - 0.78v
Still nothing on external meter. I do see a stronger signal on the monitor radio (almost full scale). I can barely hear my modulation, but it's crackly and not understandable.
Nothing got hot at all.
Base of driver - 0.21v
Base of final - same as driver
Seems like the power is there now, just not registering on meter. Still receives strong.
Went ahead and replaced tr45 with a new one.
Now:
Base - 1.51v
Collector - 8.28v
Emitter - 0.78v
Still nothing on external meter. I do see a stronger signal on the monitor radio (almost full scale). I can barely hear my modulation, but it's crackly and not understandable.
Nothing got hot at all.
Base of driver - 0.21v
Base of final - same as driver
Seems like the power is there now, just not registering on meter. Still receives strong.
Yanked out and checked:
C165
C158
C160
C166
All test around their given values.
Probed collector of pre-driver, driver and final. Pre-driver seems to be amping up and steady, final seems to amp up more and steady but the driver doesn't seem as amped up as the pre-driver or the final and isn't a steady waveform.
Checked for that .41v off TR49 in regulator area as Brandon stated I needed to, the .41v has changed to what the voltage chart states (guess fixing that pre-driver issue previously fixed that problem).
Stumped.
C165
C158
C160
C166
All test around their given values.
Probed collector of pre-driver, driver and final. Pre-driver seems to be amping up and steady, final seems to amp up more and steady but the driver doesn't seem as amped up as the pre-driver or the final and isn't a steady waveform.
Checked for that .41v off TR49 in regulator area as Brandon stated I needed to, the .41v has changed to what the voltage chart states (guess fixing that pre-driver issue previously fixed that problem).
Stumped.
Had to run do an OS conversion on another PC.
Now I'm gonna get back started on this radio.
Tip:
For all those that don't want the Windows 11, or would rather stick with Windows 10 while still retaining updates without paying the ESU fees to keep Windows 10 updated another year, then just install Windows 10 Enterprise IoT LTSC version (2021 version). This version of windows is intended for businesses, Kiosks, ATM machines. This version has no bloatware whatsoever, very minimalistic.
Note: your standard windows keys won't activate this version, you must purchase a key for this version. The updates for this version of windows will continue until the year 2032. You can get this version off the Microsoft site or Archive under NTDev user.
Just a tip.
Now back to work on this radio.
Now I'm gonna get back started on this radio.
Tip:
For all those that don't want the Windows 11, or would rather stick with Windows 10 while still retaining updates without paying the ESU fees to keep Windows 10 updated another year, then just install Windows 10 Enterprise IoT LTSC version (2021 version). This version of windows is intended for businesses, Kiosks, ATM machines. This version has no bloatware whatsoever, very minimalistic.
Note: your standard windows keys won't activate this version, you must purchase a key for this version. The updates for this version of windows will continue until the year 2032. You can get this version off the Microsoft site or Archive under NTDev user.
Just a tip.
Now back to work on this radio.
Last edited:
I mirrored my operating systems. I got tired of reinstalling all my programs, drivers, radio software etc, and then trying to remember how to configure my SFTP and all the other stuff. Now, when things go haywire, I just slide in the drive with my OS containing my mirroring software and images, boot to that, and restore my imaged OS on the original drive (or its replacement). Restart computer and its like new, the way I like it. The nice thing is It don't mirror empty space, so different drive sizes can be used when restoring. Security updates are great, but not at the expense of putting a time limit on purchased software. I'd rather just be careful and not store sensitive stuff on my attached HDD.
And they are catching on to this, so to get everyone on the subscription system, new hardware will soon be incompatible with old operating systems. Keep those CPU's/GPU's cool and don't turn on your computer when the house is only 40 degrees F. If you are lucky, some capacitors will limp your computer along until you go. Thats my plan anyhow because Im done playing microsofts games.
And they are catching on to this, so to get everyone on the subscription system, new hardware will soon be incompatible with old operating systems. Keep those CPU's/GPU's cool and don't turn on your computer when the house is only 40 degrees F. If you are lucky, some capacitors will limp your computer along until you go. Thats my plan anyhow because Im done playing microsofts games.
Back on the 55v...
The driver, after removing leads from the board is showing as a PNP transistor, whereas the final after removing leads from the board is showing as an NPN. Using multimeter set to diode mode. Used the parts radio to confirm everything else.
Getting 27mhz to the pre-The driver, collector of both driver and final although the 27mhz signal wasn't very stable on the driver.
C165
C166
C160
C158
All check out as valued, after removing from circuit.
Inductors in RF section checked and replaced if needed.
All resistors in RF section checked and replaced if needed.
TR45 now shows right voltages on all leads.
Regulator section now shows proper voltages (even TR49).
Voltage on the Collector of driver and final correspond to VR13 position and changes when turning VR13. As does the collector of the Passthrough regulator.
When using oscope to check amplification of pre-driver, driver and final, the pre-driver was strong and steady, the final was steady and the same strength as the pre-driver, but the driver was weaker than both the pre-driver and final and wasn't stable.
I'm assuming the driver is either fake or something messed it up while I was fixing other things in the circuit.
The driver, after removing leads from the board is showing as a PNP transistor, whereas the final after removing leads from the board is showing as an NPN. Using multimeter set to diode mode. Used the parts radio to confirm everything else.
Getting 27mhz to the pre-The driver, collector of both driver and final although the 27mhz signal wasn't very stable on the driver.
C165
C166
C160
C158
All check out as valued, after removing from circuit.
Inductors in RF section checked and replaced if needed.
All resistors in RF section checked and replaced if needed.
TR45 now shows right voltages on all leads.
Regulator section now shows proper voltages (even TR49).
Voltage on the Collector of driver and final correspond to VR13 position and changes when turning VR13. As does the collector of the Passthrough regulator.
When using oscope to check amplification of pre-driver, driver and final, the pre-driver was strong and steady, the final was steady and the same strength as the pre-driver, but the driver was weaker than both the pre-driver and final and wasn't stable.
I'm assuming the driver is either fake or something messed it up while I was fixing other things in the circuit.
Last edited:
Wanted to give some input before I throw this good driver and final in here.
With the driver and final out of circuit, testing solder pads where driver/final goes in transmit mode with volt meter:
Driver
Base - 5.23v (kind of high I think)
Collector - 2.89v
Emitter - 0.00v
Final
Base - 0.00v
Collector - 2.89v
Emitter - 0.00v
Now with oscope:
Driver
Base - 27mhz strong (same as pre-driver collector on scope) and steady
Collector - 27mhz strong (same as base) and steady
Emitter - zip
Final
Base - zip
Collector - 27mhz not strong but steady
Emitter - zip
Pre-driver voltmeter
Base - 0.93v
Collector - 10.1v (kinda high I think)
Emitter - 0.93v
Scope pre-driver
Base - 27mhz medium strength but steady
Collector - 27mhz strong and steady
Emitter - zip
With the driver and final out of circuit, testing solder pads where driver/final goes in transmit mode with volt meter:
Driver
Base - 5.23v (kind of high I think)
Collector - 2.89v
Emitter - 0.00v
Final
Base - 0.00v
Collector - 2.89v
Emitter - 0.00v
Now with oscope:
Driver
Base - 27mhz strong (same as pre-driver collector on scope) and steady
Collector - 27mhz strong (same as base) and steady
Emitter - zip
Final
Base - zip
Collector - 27mhz not strong but steady
Emitter - zip
Pre-driver voltmeter
Base - 0.93v
Collector - 10.1v (kinda high I think)
Emitter - 0.93v
Scope pre-driver
Base - 27mhz medium strength but steady
Collector - 27mhz strong and steady
Emitter - zip
Gonna wait to throw this other final and driver in until I hear back from you two guys on the above results with no driver/final in circuit, in transmit mode with pre-driver in circuit.
Going over the schematic I noticed C175 should be a 680pf, but what's in this one is a 560pf. Would this much of a drop cause the base of the driver pad (without driver installed) to show 5.23v? What should the base voltage of the driver pad be without the driver installed?
After replacing R220, R221, C174:
Final and driver not installed. Tests done in TX mode
Pre-driver:
Base - 1.15v
Collector - 11.02v
Emitter - 0.93v
Driver solder pad:
Base - 6.04v
Collector - 2.89v
Emitter - 0.00v
Final solder pad:
Base - 0.00v
Collector - 2.89v
Emitter - 0.00v
What you guys think? Should I throw the driver and final in and try it with the results I have above, or do you guys see something I should look into first?
Final and driver not installed. Tests done in TX mode
Pre-driver:
Base - 1.15v
Collector - 11.02v
Emitter - 0.93v
Driver solder pad:
Base - 6.04v
Collector - 2.89v
Emitter - 0.00v
Final solder pad:
Base - 0.00v
Collector - 2.89v
Emitter - 0.00v
What you guys think? Should I throw the driver and final in and try it with the results I have above, or do you guys see something I should look into first?
Check the inductor to ground on the driver base, make sure it didn't open up.