SDS200 - GPS port pinout?

Status
Not open for further replies.

bob-k

Member
Joined
Jul 19, 2011
Messages
92
Location
Colfax NC
It appears to be 3.3v TTL logic and not RS-232.

I have never used GPS with an SDS so not really sure how it behaves. I've only ever used a regular HomePatrol 1. With those the GPS indicator turns green if data is present and good. It also asks you if you want to use GPS.

This thing just seems to show GPS in white and it forces it to be used. I unplugged my test GPS and set the radio to California (I'm in Kansas) using the full database. When I plugged the GPS in the radio selected Kansas and started scanning that. Is that how it is supposed to behave? What if you don't want to use GPS? Do you have to unplug it?

I have had one made for me with use for my SDS100 (Sold) Now I seek one for the soon to arriving SDS200. It worked great!! I need sell the older one!
 

EricCottrell

Member
Premium Subscriber
Joined
Nov 8, 2002
Messages
2,413
Location
Boston, Ma
Hello,

One possible problem with the GlobalSat BR-355S4 is it may require a 5 volt input. The SDS-200 has 3.3 volts on the connector. You need a serial GPS module that can be powered with 3.3 volts.

73 Eric
 

nessnet

Member
Premium Subscriber
Joined
Jan 22, 2007
Messages
1,732
Location
Eastside of Lake WA
I don't want to run afoul with Uniden over it so no not really. I just made up a couple from some extra parts I had around.

I don't think Jon ever did get hassled by Uniden.
And Paul certainly was aware of him, he was not shy promoting his stuff...
He got in S#@! because of a (bonehead) move at work....

Go for it.
 

k4hg

Newbie
Premium Subscriber
Joined
Mar 9, 2015
Messages
2
If anyone is looking for a cheap way to do this, you can pick up a UBlox 6M on an interface board for less than $7 on ebay (add a couple more dollars if you want a US seller with faster shipping time) and dig up an old phone cable with 4 wires. The latter was the hard part for me since I haven't had a landline for 10 years - finally found one wrapped up around an old DSL modem. The wiring diagram early in this thread is correct, but use pin position and not wire colors - in mine the wire colors were reversed: power was red/black but black was positive. The UBlox is perfect with 3.3v VCC and IO. Don't waste your money on a UBlox 7 or 8, these are newer and more powerful, can do multiple constellations (GLONASS etc.) and give more precise positions, but you don't need it in this application. The 6M is a very good module, I get solid lock inside a house with a metal roof. Look carefully before you buy one of the pre-made sensors. These are tempting because they look good but most are configured to communicate via I2C and have a built-in magnetometer for use on drones.
 

peteinsf

Member
Joined
Jun 9, 2003
Messages
32
Location
SF
just confirming. This is a narrow "RJ9" headset jack? (not a 6 pin RJ11 using just the 4 center pins)
 

UPMan

In Memoriam
Premium Subscriber
Joined
Apr 19, 2004
Messages
13,296
Location
Arlington, TX
Technically, this is called an RJ14. Same size as RJ11, but RJ11 only uses 2 conductors. RJ14 uses 4. And, RJ25 uses all 6.
 

mancow

Member
Database Admin
Joined
Feb 19, 2003
Messages
6,879
Location
N.E. Kansas
I measured 3.8v on mine. It appears to be 3.3v logic but not sure if it's 5v tolerant. I would stay with 3.3v devices.
 

6079smithw

Member
Joined
Jun 20, 2004
Messages
437
Location
Near the Biggest Little City
1: GPS TX
2: Ground
3: GPS RX
4: V+
Thank you, Sir!

In case anyone's interested, I parallel-wired a Garmin GPS 18PC (externally-powered) to a friend's '200 and it works perfectly with his Icom IC-2730A (APRS). Did the same thing a while back with my Kenwood 700 and 536HP. Performance on both scanners seems equal based on a 75-mile road trip.
 

N9PBD

Member
Premium Subscriber
Joined
Aug 24, 2003
Messages
535
Location
Southern Illinois (Metro St. Louis)
Hello,

I used a 3.3 volt NMEA module without any problem. The data input and data output are TTL like levels. This module works great and the battery backup speeds up position lock.
Adafruit Ultimate GPS Breakout - 66 channel w/10 Hz updates

The board will fit into a single RJ-14 surface mount keystone box.

73 Eric

Eric,
Was the 3.3v present on the jack all the time? I'm only getting +1.44VDC between GND and V+ on my SDS200.
Greg
 

EricCottrell

Member
Premium Subscriber
Joined
Nov 8, 2002
Messages
2,413
Location
Boston, Ma
Eric,
Was the 3.3v present on the jack all the time? I'm only getting +1.44VDC between GND and V+ on my SDS200.
Greg
Hello,

Voltage was present while the scanner was on. It sounds like something is loading down the circuit or you did not get the pin numbering right. Try measuring each pin on the jack to the chassis.

73 Eric
 

N9PBD

Member
Premium Subscriber
Joined
Aug 24, 2003
Messages
535
Location
Southern Illinois (Metro St. Louis)
Hello,

Voltage was present while the scanner was on. It sounds like something is loading down the circuit or you did not get the pin numbering right. Try measuring each pin on the jack to the chassis.

73 Eric

Thanks for the reply Eric,

I double checked the numbering on the connector, against both what @mancow and what @UPMan posted in this thread. I'm thinking my SDS200 will be taking a trip back to the mothership.

73, Greg
 
Status
Not open for further replies.
Top