TackTick T122 NMEA interface not repeating DPT input

[allene]

I have a TackTick T122 nmea interface. I have a computer hooked up to the T122 NMEA out and NMEA2 input. I have an Airmar smart depth connected to the NMEA1 input also labeled GPS. I am not getting DPT sentences from the NMEA output as I should according to the manual.

My system is basically a T104 without the T912 plus the Airmar DT820PV-235-0
Here are some examples:

NMEA input 1 (Airmar Smart Depth nmea-0183)
$SDDPT,2.0,*7B
$SDDBT,6.9,f,2.0,M,1.1,F*0B
$YXMTW,22.5,C*17

NMEA input 2 (computer)
$PTAK,TWC,0.0,2*7E

My problem is I do not get the DPT sentences repeated even though the manual for the T122 says they will be transmitted.

NMEA Sentences (0183 V2.30)
Received Sentences: DBT, DPT, GLL, HDG, HDM, MTW, MWV, RMB, RMC, VHW, VLW, VWR.
Transmitted Sentences: DPT, GLL, HDG, MTW, MWV, RMB, RMC, VHW, VLW, VWR.
Note: Only information available will be transmitted.

Here is what I read from the nmea output (computer)
$IIMTW,+20.0,C*3A
$IIMWV,080,R,09.2,N,A*10
$IIMWV,105,T,09.8,N,A*10
$IIVHW,,,155,M,04.7,N,,*66
$IIVLW,00689,N,007.2,N*51
$IIVWR,077,R,09.2,N,,,,*6A
$IIHDG,155,,,14,E*16

I want the computer to be able to read the DPT data and the manual says it should be transmitted.

How can I get the T122 to transmit the DPT data?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Allene,

Have you been able to verify that the TackTick instruments are able to successfully display depth data from your Airmar DT820PV-235-0?

[allene]

Yes. Depth is displayed on any of the TackTick displays. This has to be from the Airmar as there is no other depth hooked up.

Also, I do not get any of the GPS type displays even though I am inputting GPRMC sentences. These also do not repeat.

[Chuck - Raymarine - Moderator]

allene,

I have transmitted the sentences which you have provided to the T122's NMEA 0183 IN2 port and have verified that the TackTick display is reported the received depth value. Unfortunately, it appears that the T122 did not transmit DPT sentence along with the other NMEA 0183 sentences transmitted by the T122. A problem report has been submitted to seek correction of this problem. Until such time as a correction is issued, it is recommended that this problem be worked around paralleling the NMEA 0183 output from the NMEA 0183 source of depth data and then interfaced the paralleled output to the NMEA 0183 input port of the NMEA 0183 listener which in turn requires this data.

With respect to the RMC sentence, I have verified that when the RMC sentence (multiplexed with the DBT sentence which you had provided) is received via the T122's NMEA 0183 IN2 port, then the TackTick display repeats the received GPS data and I also verified that the T122's NMEA 0183 output port transmits NMEA 0183 sentences containing GPS data.

[allene]

My guess is that when the hull transmitter is in the system, that any speed or depth inputs are not transmitted even if no depth is coming out of the hull transmitter.

I will come up with a work around. I just didn't want to do that until it was confirmed that my unit was not defective. Thank you for confirming that.

RMC was working today. IIRMC is repeated along with IIGLL and all the GPS functions display. It must have been an intermittent connection as without changing anything except probing the inputs, it started working. I will keep an eye on it.

[Chuck - Raymarine - Moderator]

allene,

You're welcome and thanks for the additional information and suggestion concerning the hull transmitter. For clarity in the problem report, has a depth transducer been interfaced to your hull transmitter?

[allene]

You asked "has" a depth transducer been interfaced. It was almost three years ago when I first bought the system but it has not been since I installed the Airmar Smart transducer.

When I had the TackTick depth transducer installed it was not accurate on starboard tack because of the deadrise (angle) of the transducer. My boat is wood and there was no way to mount the transducer level. I replaced it with the Airmar smart transducer which has an angled transducer.

For the last few years there is nothing hooked up to the hull transmitter depth input.

So if your question was "is" a depth transducer interfaced to the hull transmitter the answer would be no.

I hope this answers your question.

[Chuck - Raymarine - Moderator]

Thanks for the confirmation.

[allene]

Is there any chance this will be fixed and if so, what timeframe?

[Chuck - Raymarine - Moderator]

allene,

To date, there have been no software updates issued for the TackTick instrument line.
As this is the first such reported of this issue, it may take additional affected users to justify the change. That said, the problem will not be reviewed the by engineering team for a couple of weeks. Any resulting software update would not likely be available until the 2018 boating season.