800 MHz receive module in Kenwood TM-733A
Steve Haehnichen
diagram labeled:
800 MHz Front-End: KCB28 (Tx-Rx Unit B/4 IC202) Except K, P Type.
(What is type K, or P?)
It's an internal schematic of IC202. The external connections are:
RF
E (10 of these, all grounded)
IF (MCF on schematic)
L0 (HET on schematic)
Vcc (80R on schematic)
From the 430 MHz module schematics, it looks like the RF line is
connected to the antenna via three capacitors (in series) and two
inductors (to ground). That small section is outlined with a dotted
box and marked "*B", leading me to suspect it's not installed on all
radios. Wouldn't be hard to add..
The MCF (IF) pin 7 is mixed into the UHF signal just before the BPF.
Pin 13 (L0, HET) goes into some kind of rectifier module I don't
understand. Pin 14, interestingly named Vcc and "80R" goes to Q203, a
power switching transistor, which is controlled by IC206, a "Shift
Register".
This Shift Register has outputs for:
14R (144 MHz?)
80R (800?)
43R (430?)
36R (360?, goes to IC203, "36RF", which seems to do 440 as well)
FAN (yep, Fan power transistor)
MID
NI (both go to Mid/Low switching)
Sooo.. I guess the questions that come to mind are:
1) Do US radios have this 800 MHz module installed?
2) How does one ask the microprocessor to enable that output of the
shift register?
Happy Hacking!
-Steve "I'd never listen" Haehnichen
Steve Haehnichen Vigra, Inc. San Diego, CA
st...@vigra.com (619) 597-7080 x116 Fax: (619) 597-7094
B2 BASD
Haehnichen) writes:
Steve:
I think t
he K & P are part of the code that Kenwood uses to designate the country
or market that the radio is configured for. I beleive "K" is the US. I
don't know what the other market codes are, maybe Canada is "P". Look on
the box that your radio came in and on the sticker that has the s/n there
should be a "K" somewhere on the sticker.
Does anyone have the complete listing ???????
Thanks, Greg at Nortrop via AOL
Steve Haehnichen
> I think t he K & P are part of the code that Kenwood uses to
> designate the country or market that the radio is configured for. I
> beleive "K" is the US. I don't know what the other market codes are,
> maybe Canada is "P". Look on the box that your radio came in and on
> the sticker that has the s/n there should be a "K" somewhere on the
> sticker.
> Does anyone have the complete listing ???????
Yep! I missed it earlier. It's right inside the front cover of the
service manual. Here's the table, rounded to the nearest MHz:
K North America
P Canada (as if it weren't in North America)
Tx 144-148 438-450
Rx 118-174 410-470
M "Other countries"
Tx & Rx 144-148 430-440
M2,M3 "Other countries"
M4 China
Tx 136-174 410-470
Rx 118-174 410-470
E,E3,E9 Europe
Tx & Rx 144-146 430-440
E2 Europe
Tx 136-174 410-470
Rx 118-174 410-470
The only difference between the K and P models seems to be that they
include different warranty cards: B46-0410-30(K) vs. B46-0422-00(P).
So... where are the country select bits? :-)
-Steve
wilso...@gmail.com
Channel Jumper
wilso...@gmail.com;803022 Wrote:
> Thanks for putting this information on the net, even though it is 19
> years old! I am wanting to buy a TM-710A and I'm trying to figure out
> how much the output power is so I won't over blow my amp!
>
> diagram labeled:
>
> 800 MHz Front-End: KCB28 (Tx-Rx Unit B/4 IC202) Except K, P Type.
> (What is type K, or P?)
>
> It's an internal schematic of IC202. The external connections a
> E (10 of these, all grounded)
> IF (MCF on schematic)
> L0 (HET on schematic)
> Vcc (80R on schematic)
>
> From the 430 MHz module schematics, it looks like the RF line is
> connected to the antenna via three capacitors (in series) and two
> inductors (to ground). That small section is outlined with a dotted
> box and marked "*B", leading me to suspect it's not installed on all
> radios. Wouldn't be hard to add..
>
> The MCF (IF) pin 7 is mixed into the UHF signal just before the BPF.
> Pin 13 (L0, HET) goes into some kind of rectifier module I don't
> understand. Pin 14, interestingly named Vcc and "80R" goes to Q203, a
> power switching transistor, which is controlled by IC206, a "Shift
> Register".
>
> This Shift Register has outputs for:
> 14R (144 MHz?)
> 80R (800?)
> 43R (430?)
> 36R (360?, goes to IC203, "36RF", which seems to do 440 as well)
> FAN (yep, Fan power transistor)
> MID
> NI (both go to Mid/Low switching)
>
> Sooo.. I guess the questions that come to mind a
> 2) How does one ask the microprocessor to enable that output of the
> shift register?
>
> Happy Hacking!
>
> -Steve "I'd never listen" Haehnichen
>
> Steve Haehnichen Vigra, Inc. San Diego, CA
> st...@vigra.com (619) 597-7080 x116 Fax: (619)
What kind of amp are you talking about?
I'm not aware of any band plan that includes 800 MHz transmit for the
amateur radio service!
There is a segment in the 900 mhz - but that is a horse of a different
color.
If this is a USA comment, it would be illegal to use it on another radio
service while using it for the amateur radio service.
The bottom line is - if you wanted to receive with it, you could do the
same thing with most any cheap Uniden Bearcat type scanner.
Is this the modification you are talking about?
http://www.radiomods.co.nz/kenwood/kenwoodtm733.html
--
Channel Jumper