WT

WT419 and charger WT419 and motorcycle headset/PTT

The WT-419 is a UHF CB handheld manufactured by Tsuen Shing electronics in Honk Kong that is ideal for motorcycle to motorcycle communications or use in the outdoor environment. It is a 2 Watt RF output UHF CB 40channel radio with CTCSS capability, repeater function for all those range enhancing repeaters, key lock ,so you can stuff it in to your jacket pocket and not have it jump to another channel , A great feature termed "power off" function ( turns it self off after a user definable time ( in hours) so make sure this time duration setting exceeds your ride duration !! ) Vox capable with three levels of sensitivity (but I'm a very disappointed at its very slow attack time) . Selectable RF output power of 500 mW or 2W for that extra required range. The Radio comes supplied with a charger and 4 rechargeable 1600 mAh
NOTE: due to the variation in performance of NiMiH batteries the batteries will not have a warranty we are tempted to sell the radio without rechargeable batteries !

NiMih batteries , and an earphone/mic , although there is no reason you cant use standard AA alkaline batteries if you had to ,we advise that if you are going hunting in the bush you take a spare set of four AA alkaline batteries in case your rechargeable ones go flat ! .

We often have people ringing up grizzling that the batteries wont hold their charge , We always get the system back to check and find the user has been running on High power and expecting the radio to run all day with normal use , The radio will run all day with normal ( see the manual specifications of suggested receive transmitt and standby times) use on 1600ma cells and set to 0.5W rf output , However if you are going to run the radio on high power 2W Rf out then the cells are only going to last a quarter of the time they last on 0.5 W, At 2W ,during transmit, the radio is now consuming 4 times more energy per unit time , from the battery than on 0.5 W transmit . .. Remember the handbook says a 13Hr charge for 1600mA cells ,this is governed by the maximum current the radio charger will supply to the batteries . If you are using 2500mA cells, then they will need a lot longer to charge, at least another 7 hrs ! if this is not suitable and you need to use the radio before this charging time then I suggest you purchase one of the fast chargers from Dick smith, Jaycar , Altronics etc etc ,, Remeber also that NiMH cells have a high self disharge rate compared to other cells ie Alkaline, and dont be surprised that if the radio is put away fully charged and pulled out a month later the cells will be completely flat and need a recharge this is an undesirable feature of NiMH system.

Never try and charge Alkaline/NiCad/Carbon Zinc batteries in this radio, you will stuff the radio and burst the batteries and perhaps injure yourself and neither is covered by warranty !

WARNING : Be careful when you are using it on a motorcycle headset or external earphone , this radio has been modified to our specifications and it can be very loud in your ear using a headset , don't turn it up loud when you first turn it on or it will blow out your ears or possibly damage the earspeakers , and neither problem is covered under the warranty!   The connections for this radio's headset are, 2.5mm stereo headset, plug tip is mic, ring is speaker and sleeve common. 3.5mm mono plug for PTT switch ( 3.5mm stereo plug for external battery charger )
        The radio is also water and dust proof to standard IP52 (not IP54 ) which is good for the motorcycle environment .This means it will be ok in a shower of rain however please note that IP52 is NOT enough for it to be waterproof and it may get some water seeping in if your were riding in the heavy driving rain for more than 30 mins . It would still pay to pull a plastic bag over it or wrap it in Glad wrap to offer it better protection, then I'm sure it would be perfectly ok even if rain did seep in around the plastic wrapping . This radio would be great if you were out hunting or on the farm as well you as you don't have to worry about the radio getting rain wet when using it ! however you could not drop it in the river and expect it to resist the ingress of water .

4 1600 mAH NiMiH rechargable cells radio in supplied charging base with pwr pack

AS-419 Single Charging Stand Operation Flow

1. Plug in the adapter into the AC outlet and connect to the single charging stand.

2. The red LED indicator of the charging stand will light up; indicating the power of the charger is on.

5. Put the 2-way radio into the single charging stand, the green LED (on the charging stand) lights up and blinks (every 5 seconds) stating that the unit is processing the charging mode.

6. The green LED will be off and the red LED will remain when the 2-way radio is fully charged.

see bottom of page to use "alternative brand" Nickel metal Hydride batteries in this radio

VEHICLE CHARGING ADAPTER: (car/motorcycle)
Unfortunately , you cant charge the radio and talk on it at the same time .. however it can be charged off a 12 Volt only ( NOT 24 Volt) negative earth cigarette lighter socket , We have a charging cable to do this with a 3.5mm stereo plug on the end . (ask us about this !! ) $NZ 15.00

Channel 22 and 23 are reserved for Telecontrol and data only, these channels have been blocked to comply with the Australian regulations . (you still have 38 to choose from !!) BUT! see below

The NEW shipment (Dec 2006) of WT419 is able to be opened on the blocked channels in the hidden menu as shown below ! ! !

Press "PTT", and the "CALL" key simultaneously and rotate the volume key at the same time and wait for 3 seconds to turn on the unit. "0000" will display.

Press "Up" or "Down" key to go to "Au22" menu and then press "Enter" key.

Press "Up" or "Down" key to select "On" or "Off".

Press "Enter" key to confirm and back to "0000" display.

Press "Enter" key to go back to normal display.

Channels 5 and 35 may not have CTCSS or calling function ( CTCSS and Calling tones are blocked on these radios)

This is not a New Zealand Requirement but since this product is registered for sale in the large Australian Market , the Tone call cannot be activated for more than 3 seconds in any 60 second period ie you can tone call once but have to wait 60 seconds before you can call again.

Water Ingress
If you ever drop a cell phone or walkie talkie into the water you must take out the batteries as soon as you possibly can, as if there is any electricity floating around on a wet circuit board ,electrolysis will begin to eat away at the copper connections and dissolve them , electrolysis will chew away the pins on integrated circuits and IN AS LITTLE AS 30 MINS and the appliance will be rendered unfixable! Take those batteries out pronto! and before you pull the device to bits to dry it out. In fact if you drop a cell phone or radio into sea water, pull out the batteries immediately , then dump the wet appliance into fresh water and give it a good soaking to dilute the salt contamination off the circuit board and components ( you cant make things worse by trying this , a radio has a much better chance of going again if its had freshwater contamination than if it was dried out after salt water contamination as the salt residue can short circuit connections!)

Performance:
I have done some electrical tests on it to assess its performance and I am quite impressed. In this test I used a 5.7Volt power supply as a voltage source. On receive it seems to trickle along at about 70mA squelched and 90 mA un-squelched at easy listening volume, Though I suspect it probably has a low power receive standby mode which it drops to after a time of inactivity . The menu selectable mute opens at a very respectable -125 dBm ( close to the lowest RF output on my HP8656b signal generator) there is a facility to have two squelch settings 1, opens at -119dBm and 2,( more sensitive) opens at -125 dBm, I have measured the RF output using the Agilent E3304B spectrum analyser and found +27 dBm (500mW) on low power and +33.25 dBm (2W) on high power so it has quite a useful range of output .
You can immediately double the range by switching from 500mW up to 2W ( it requires a 6dB ( four times) increase in power to double the range on a transmitter and get the same received signal strength at the other end ) There is a price to pay with a high powered radio and that is current consumption. Low power was 300 mA and High power was 1200 mA hence the need to supply rechargeable 1600mAh NiMHi cells as standard. The handbook quotes a useful operating time as 13 Hrs continuous on a 5%transmit 5% receive 90% standby time scale , recharge time to full capacity is 7 Hrs . I have not equated this to user time in days while riding before having to recharge. Always have 4 new AA alkalines with you in case you have the misfortune of flattening the rechargeable batteries half way through a ride ,I suggest you upgrade these cells to 2400mAh to maximise talk time at the 2 W level , dont forget to peel the plastic off the negative end of the horizontal battery !!
The rubber buttons on the front are not too small and I do like the fact it has a volume control on the top and not the usual menu selected volume push button system . Although in the model I assessed, I found the audio output level to the earphone being somewhat lacking in volume , I think the manufacturer may have deliberately padded down the earphone volume so as to not blow up the earphone or users ears ! ( turns out they did !I have seen the circuit diagram but I have asked that our shipment have the appropriate series resistor removed so that there will be adequate volume in the motorcycle headset !) all have since been modified at production time .( I have tested the new modified model and it can be very loud so be careful !)

Note : If you are going to use an external speaker on this radio then it MUST have a resistance of more than 16 ohms or the audio out put will be distorted ! (But not a problem in the shipment late Dec/Jan 2006 as the resistor is inside the radio !! )

Select the wanted function by stepping through the LCdisplay options ie Ch, channel . Cod Subtone code number. Sca, Scan all channels. Sq squelch level setting . Vot Vox ,select three sensitivity levels. Mon , disables squelch settings . ton , calling tone selection. Pow , power setting lo= 0.5 W Hi= 2.0 Watts . Rog ,end of over Beep, off-on. Pof time selection for auto switch off.
Select the required option , press the triangular Enter button , change the parameter using the up/down buttons, then confirm the selection by pressing the Enter button again.

Problems solving "
Quite a few people ring up saying their radios dont go.( wont talk to each other) and they are usually half right BUT also half wrong . Most of the time the problems are best described as "Finger Trouble" provided it has had an overnight charge and the radio is not giving "double beeps " indicating a flat battery, then it is usually one or two things . Read the manual thoroughly and follow its setup instructions . We find two major problems providing both of the radios are on the same channel ie Ch 01 ,

1. both radios must have the same CTCSS sub-tone number eg 22 ,33, 01 what ever , the CTCSS is an additional selective setup so only radios with the same sub-tone (1-38) number will respond to each other , or disable it by selecting ctcss sub-tone 00 .

2. Make sure the Function button has not switched on the Repeater function ,( small round ring with a dot in the centre appears on the LCD display top Right hand corner.) This repeater button only works for the first 8 channels , when you press the PTT button , you will see the display change to a channel number in the 30's range ,this is the repeater shift . Necessary to work through a repeater to boost range but the two radios will not talk to each other if this function is enabled. turn it off ( dot with circle on LCD gone ) .

Range: This is the million dollar question , Range in UHF radios is usually quoted under optimum conditions ie Line of sight , unobstructed pathway between the radios . In fact with most small 500mW walkie talkies ie 40 ch UHF radios ,their unobstructed range is quite phenomenal ie top of Mnt Taranaki through to Mnt Ruapehu providing its line of sight would be no problem . However, get these radios down at ground level and other factors come into play , Signal absorption by bushes ,trees , foliage, long grass all soak up precious signal and also reflections off the ground out in front of the user can cause interference of signals , all adding to reducing range. You could be getting 8 Kms at a pinch out in the open plains and with the same radios in dense bush have a problem communicating 500m !! Keeping the radio in your pocket up close to the body will shield the radio from receiving signals ,If practical, they are best left sitting up high somewhere where their antenna has a good all round "View" , Don't forget to pick up the radio before you move away !!! Use of the loud warbling "tone Call button" is beneficial in these circumstances , if the radio is not immediately close to your ear . Sometimes, if the signal is a bit scratchy, reception can be improved by listening to the radio held as high above your head as possible to try and improve the received signal. UHF signals do not bend over hills, hence if you are only half a kilometer apart with a high hill between you, the signals may not bend over and flow down to the other radio and you may not have contact, however if you are in a large mountainous valley, you may find the signals bounce around and you may be surprised as to where you can communicate! .
It is best to use the radio on its lowest power setting 0.5W, this is much easier on batteries , when you switch to high power (2 W) the transmitter really sucks up the power and your batteries will not last too long, ( depending on how long you actually talk for) so if you can talk on 0.5 W, use it . Note, switching from 0.5W to 2 W will double your effective communication range given the rest of the variables remain constant . ( but flatten the batteries 4 times faster!)

Price : ?? new stock , due to currency fluctuations ,increase transportation the price is now NZ $100 each plus postage ,which is still well under any 2Watt handheld on the market!! and it comes supplied with rechargeable batteries! (NOTE: due to the variation in performance of NiMiH batteries , the batteries will NOT have a warranty ) but it will require its own motorcycle headset plug!! and we have 0rdered 300 motorcycle headsets to suit, yes another bloody headset connector change ! why cant you manufacturers standardise!
Vehicle charging adapter for 12volt negative earth vehicle $NZ15.00

Warranty The WT419 will have a 6 month warranty for the radio, base charger , and wall plug power supply. The warranty covers electrical defects only , and not mechanical breakages . If there is signs of neglect ,water damage , misuse, unauthorized tampering , the warranty will be null and void . However we are happy to honor this warranty if for some reason the radio fails ( we just give you another one !!) ! we will not provide a warranty on the rechargeable batteries in fact we are tempted to sell the radio without rechargable cells and it would still be a very inexpensive 2W radio !!

On no account try to charge any other type of battery other than Nickel Metal hydride batteries in this radio ,This radio and its base/internal charger will only charge Nickel Metal Hydride batteries safely , there is a real risk of damage to the radio and possibly yourself should the incorrect type of cells be overcharged and burst !! do not try to charge Nickel cadmium, Alkaline ,or Carbon-Zinc cells. There is a simple modification that needs to be done to only one of the "other Brand" NiMH batteries and this battery will enable the proper charging process (winking green light ) . Peel off the plastic covering of one battery from the lower half only and this will expose the metal case of the Nickel Metal Hydride battery. (see photos below) Take the back off the radio to reveal the 4 batteries, remove the batteries. If you look into the top horizontal battery compartment without the batteries in place , you will see at the spring (-ve) end of the battery contact and in the bottom/floor of that horizontal compartment , at the conical spring end, a flat metal contact that pokes up out of the floor and presses against the inserted battery case. This is the "sensor" that tells the radio it has the original nickel metal Hydride batteries in place.
note: The original green batteries supplied are missing the plastic battery covering at the flat (negative) end of the cell . The sensor contact in the horizontal battery compartment, detects this bare metal and tells the internal charging circuit to initiate the charging process . If this contact does not touch metal of the battery case ( ie there is still plastic wrapping ) then charging is inhibited and no winking green light .

new , original, modified new. sensor contact to enable charge modified cell in position

For those who are interested, the radio complies under AS/NZS 4365- 1996,
EMC Technologies (NZ) Test report No. 40603.1 dated 22 June 2004 , also
EMC Technologies ( Australia) SAR Test Report No. MO40549 dated 11 June 2004 .
We also have the circuit diagrams as well !!

We offer a money back ( less postage ) guarantee with all our products ( unless stipulated like batteries) , if faulty then we will replace it or refund .BUT all goods must be returned in a saleable condition ( boxes packaging radio unblemished so it can be resold as new .). and you have 7 days to decide whether the radio will do what you want ie potential, compatibility issues , range issues etc Dont expect us to refund you after 2 months of use and the radio looks like its well used and dirty ............ its yours !!

Pinfold Health Services Ltd,1172 Arawa st, Rotorua 3201,New Zealand. ph +64-7-3488850 fax +64-7-3486555 pinfold@xtra.co.nz