Kenwood TS-950sdx SDXCC 6Kc TX Unit

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There's Modness to ar Methods!!   TS-950sdx AM Receiver Mods   There's Modness to ar Methods!!

Gotta Hear dat VOOODOOOO!!!

Read this boring 'Stuff...

Disclaimer Notice
These modifications should be accomplished by qualified personnel who
have had enough knowledge and practice in SMD soldering techniques, at the owners risk.


We are not responsible for any personal injury incurred while performing these mods.
We are not responsible for any damage to, or illegal operations of the equipment as a result of the mods,
mod errors, or possible mod misinformation via these pages.

The Radio modifications shown here are provided for properly licensed operators only.
The user is solely responsible for making sure that any modifications made to
the radio unit must meet all Federal and State Regulations for the Country of use.
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Modifications are provided for information purposes only.
Although the greatest care has been taken while compiling these documents,
we cannot guarantee that the instructions will work on every radio presented.

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Gotta have PARTS!!!

390pF - You will need 1ea of these
805 SMD Chip Capacitor
Digikey - 478-1323-1-ND ---- 08055A391JAT2A
1uF - You will need 1ea of these
805 SMD Chip Capacitor
Digikey - 490-4736-1-ND ---- GRM21BR71H105KA12L

AM Detector Circuitry:

The TS-950sdx uses a Diode Charge Pump (DCP) as an AM Detector located on the Signal Unit.
The demodulated AM signal is then passes thru some RC timing and a Low Pass Filter to shape the Audio.
The First Low Pass Filter consists of R97 and C65. This is a 27K ohm resistor with a .01uF cap to ground.
This creates a center frequency of about 600Hz.
C65 needs to be changed to a 390pf to give a new center freq of 15Kc.
The signal then goes throu C75, a .1uF coupling capacitor that rolls the lows off at about 100Hz.
This capacitor needs to be changed to a 1uF to give a new roll off frequency of about 20Hz.
This opens up the Fidelity of the AM reception a phenomenal amount!
The new AM Frequency Response is from 20Hz to 10Kc.

Now that the AM Receiver is Hi-Fi, you might notice that when you listen wide (10Kc or wider)
You hear a whistle or a whine. This is the heterodyne from the next station over 10Kc.
The older AM receivers came with 10Kc Heterodyne Notch Filters to take out that whine,
But unfortunately the SDX does not have that. It was designed only to receive at 3kc so it didn't need it.
You can use the IF VBT to shift the IF slightly and filter the whine out.
You can also use any of the Analog Filters, then use the IF VBT to shift those filters.
The SDX is a wonderful AM receiver once you learn all the tricks!!

Reference the pictures below to locate and change the capacitors on the Signal Unit.

AM Mod Location
Here is a Pic of the Signal Unit.
This is a far shot so you can locate the area your going to work in.

Signal Unit, C65 and C75
Here are C65, and C75.
Change C65 out to a 390pF 805 case ceramic chip.
Change C75 out to a 1uF 805 case ceramic chip.

That's it!
This was a real easy mod.
Austa La Tacos!!

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