Humminbird Sonar - Page 1
Forum section: electronics / repair

author: metrologist
author_rank: Super Contributor
timestamp: May 19, 2023, 09:22:06 pm
content: I bought a used boat that came with a Humminbird 859ci HD, but issue is some thief cut the transducer cables and made off with the ends.I believe it is this sonar but I do not have a black wire as shown in this diagram:http://forums.sideimagingsoft.com/index.php?action=dlattach;topic=5388.0;attach=8094;image(I have found pins 2 and 4 are used for side imaging transducers that I do not have)I was going to connect the wires and see if it recognizes the transducer, but...I also have a temp/speed wheel sensor. I believe this is connected via a Y cable so both run to the main transducer port, and only the speed wheel signal is used, but I have not found out this wiring. Does someone have a Y cable that they could ohm out how the pins are combined? The T/S wheel had a 4-pin square connector and black, brown, yellow, and red wires. I may be able to at least deduce which pin the speed signal goes to and ultimately ID which wire if I knew how the Y cable is wired.Note that the manual says the 900 series (only) uses a square port for the T/S wheel and the 800 series has the same square port with 5 pins. I have not found a pinout for that or what it's used for on the 800 series. It may just be reused hardware for multiple series to save costs.

author: metrologist
author_rank: Super Contributor
timestamp: July 25, 2023, 02:58:13 pm
content: I used a VGA cable since it has several "coaxial" configurations, and it works great.Do no know how to integrate the speed wheel, but it has GPS so not really necessary.What does this spec from the manual mean?Power Output . . . . . . . . . . . . .1000 Watts (RMS), 8000 Watts (Peak to Peak)https://johnsonoutdoors.widen.net/content/fmzkkxu5hf/pdf/manual-800ci-900ci_hd_manual_532219-1en_c.pdf

author: Swake
author_rank: Frequent Contributor
timestamp: July 25, 2023, 03:09:06 pm
content: Sounds like 1000 W would be the possible power over a longer period of time. 8000 W would be the capability for a (very) short duration only.Could translate this to it emits pulses of 8000 W in a duty cycle of 12,5%. Representing an average of 1000 W.

author: metrologist
author_rank: Super Contributor
timestamp: July 25, 2023, 07:40:13 pm
content: Still confused. I think the image updates line-by-line 5Hz. It runs on 12V system and 1A. It would have to accumulate charge and send bursts to make that amount of power.

author: thm_w
author_rank: Super Contributor
timestamp: July 26, 2023, 11:31:35 pm
content: The time the transducer is actively sending a signal is in the microseconds or low milliseconds.I don't know how they claim RMS but I guess its similar to audio PMPO ratings.A 1000W signal for 1ms every second = 1W continuous power draw at the 12V input.https://www.kongsberg.com/contentassets/1d9f652b0f344359b51dbd8ff3eba350/463777a-ea440-vertical-depth-application-note.pdfhttps://data.marine.gov.scot/sites/default/files/SMFS%200813.pdf

author: fzabkar
author_rank: Super Contributor
timestamp: July 26, 2023, 11:55:52 pm
content: Looking at page 12 of the Hummingbird manual, it would appear that the "peak to peak" figure is bogus. Take the RMS value, multiply by sqrt(2) and then multiply by 2 again. Then square the result. This is nonsense.Vpp = Vrms x 1.414 x 2Ppp = Prms x (1.414 x 2) ^ 2 = Prms x 8