Baofeng UV-82 Transmit Filter Fix
I have a collection of UV82 HTs that have spurious emissions (see Transmitter Testing). This is my attempt to fix the filter in these radios.
Last updated October 28, 2025.
Comparison of components between schemantic and the actual PCB
I identified the relevant componenents and created these printed circuit board component layout mappings:
This schemantic (original source https://fccid.io/ZP5BF-82) was used for this work.
In this process the following discrepancies where identified between the schemantic and the actual device:
- The filter group consisting of components L16, D8, D7 and C33 is missing. (L16, D8, D7 are on the front. C33 is on the back.)
- The filter group consisting of components L26 and C59 is missing. Instead of the inductor a zero Ohm resistor/bridge is being used. (L26 and C59 are on the back.)
- C51 to ground is missing. (On the back.)
- C46 which parallels L19 is missing. (On the back.)
- C43 to ground is missing. (On the back.)
- C18 to ground is missing. (On the back.)
- C39 to ground is placed. (On the front.)
- In the trace section of capacitor C171, C12, C10, C11, C9, C8 and C27 seem to be differently populated than indicated in the schemantic. (On the back.)
- C38 is on the other side from R20 when compared to the schemantic. (On the front.)
When comparing this to the internal photographs from the FCC (original source https://fccid.io/ZP5BF-82) the following where noted:
- The filter group consisting of components L16, D8, D7 and C33 is missing. (L16, D8, D7 are on the front. C33 is on the back.)
These are populated in the FCC photo.
- The filter group consisting of components L26 and C59 is missing. Instead of the inductor a zero Ohm resistor/bridge is being used. (L26 and C59 are on the back.)
These are populated in the FCC photo.
- C51 to ground is missing. (On the back.)
This is populated in the FCC photo.
- C46 which parallels L19 is missing. (On the back.) This is also NOT populated in the FCC photo.
- C43 to ground is missing. (On the back.)
This is populated in the FCC photo.
- C18 to ground is missing. (On the back.)
This is populated in the FCC photo.
- C39 to ground is placed. (On the front.)
This is NOT populated in the FCC photo.
- In the trace section of capacitor C171, C12, C10, C11, C9, C8 and C27 seem to be differently populated than indicated in the schemantic. (On the back.)
This is identical to the FCC photo.
- C38 is on the other side from R20 when compared to the schemantic.
This is the same in the FCC photo.
The UV-82L internal photographs from the FCC (original source https://fccid.io/ZP5BF-UV82L) have the same findings.
