In Uruguay, there are no restrictions on TG's use. Repeaters, mobile and handheld radios, DMO's, etc., are open to all TG's on any slot.
There are, however, some conventions for the use of TG's and for the programming of handies or mobile stations.
These are the following:
a) National TG 748 is programmed as permanent on slot 1. It is meant as a calling channel, for establishing the initial contact and facilitate QSY to a regional or user activated talk group (CXUA's). Please remember that QSO's on TG 748 block time slot 1 on almost all CX repeaters.
b) Emergency TG, 74800, is programmed as permanent on both slots.
c) It is suggested that the TG corresponding to the department's TG be programmed on slot 2 as permanent.
2-Handies and mobile radios.
-These are programmed with TG 74800 in the Rx list of all channels. No Rx list should be programmed selecting the "none" or "no Rx list" options in the programming software. This allows the emergency TG 74800 to allways be heard.
3-Hotspots and DMO gateways.
-74800 is programmed as permanent in whatever slot the hotspot or DMO uses.
- It is suggested that the TG corresponding to the department's TG be programmed on the used slot(1 or 2) as permanent.
A Cluster is a special TG (TG8, for instance) that makes a group of repeaters to act as a single repeater, where you can talk only locally, as you would on a repeater on TG9. This TG, as TG9, cannot be reached from another repeater that is not included in the cluster. No Clusters exist as yet in Uruguay.
User-activated (Tactical) Uruguay Talk Groups on Time Slot 2
User-activated talk groups, also known as "tactical", "dynamic" or "on demand" talk groups, are activated by pressing PTT once. The talk group will stay active (on the repeater it has been activated) for 10 minutes after the last activation. In Uruguay users "meet" on national or regional talk groups (e.g., TG 748,TS1) and will then agree to switch to one of the user-activated talk groups (TGs 74830, 74840, 74850, 74860). Since user-activated talk groups are used on time slot 2, this operating procedure frees up resources on time slot 1 for other users.
DB9 pin on Scott Zimmermann's STM32_DVM_PiHat board
Icom ID-880E (colors are for Yaesu CT-39 cable)
Tx audio flat
Data input to Tx
Data output from Rx discriminator
Programmable on GM300, active high on Yaesu FT-7900/7800
Tx on when this pin is grounded
GM350, not used on GM300, FT-7900/7800 or Icom ID-880
9 (12V in)
On the GM300 and similar radios, pin 13 connects to J8-5 which supplies +12V switched power from the radio on/off switch.This connection can deliver 500 mA current, fused by the 2A internal radio fuse.We recommend the use of a 3 or 5A stepdown external unit to feed the STM32/Raspberry Pi MMDVM .
Do not forget, very important: jumper 551 on A (In this position, the Rx audio on the accessory connector J3 is flat, not de-emphasized, and unmuted), and jumper 601 on B (The high speed Rx data path to the microcomputer is flat from 1Hz to 3kHz). (bottom side of radio). This 601 jumper activates/deactivates the audio low pass filter.
By making this connection, you allow the GM300 to turn on automatically after a power interruption.