# ATOM Diy module

#### debe

##### Active Member
The diode is correct. Be careful buying the 2SD1071 from China. I purchased a batch that looked genuine but did not work as they were faulty (poor Gain) obviously dodgy. Other batch from China was good.

#### tysman

##### Member
and mosorb goes across B and E on D1071? if so which way

Here you go.

#### tysman

##### Member
ok thanks do wires go on those same pins to or do they go on E and B?

#### debe

##### Active Member
Ive filled in where the wires go. The polarity is trial & error, if you don't get a good blue spark, wire it up opposite polarity. It will depend entirely what polarity the pulses are from the coil.

#### tysman

##### Member
ok and when i switch polarity does black wire go on B or do i just switch the red with the black?

#### debe

##### Active Member
Just swap the red & black wires.

ok thanks

#### dr pepper

##### Well-Known Member
Most Helpful Member
Pretty cool debe, glad to see theres some seagulls still in service, in fact probably quite a few, I just looked on ebay theres a lot for sale and parts too.
The seagull was and maybe still is one of the few outboards that you could easily carry, so if you had a tender kept outside unsecure you can just lift it off and stick it in the boot of the car.
The points from memory are not particuarly brilliant, that might have been me filing them to make them last longer, pocket money didnt buy a lot, your little circuit will no doubt make them much more reliable, and probably start a lot better too.

#### debe

##### Active Member
Seagull outboards are alive & well theres a Saving old Seagull forum, UK based.

#### tysman

##### Member
on the brown module is the .47 a uf cap like the red module?

#### TubaDave

##### New Member
It should be noted that R1 is the 2 watt resistor. R2 and R3 are the 1/4 watt. The OT posts can be confusing since R1 and R2 are the same value on the red module, and R2 and R3 are the same on the brown. For brown, R1 = 1k 2W, R2 = 2.1k 1/4W and R3 = 1k 1/4W.

#### WisconsinOutboards

##### New Member
The diode is correct. Be careful buying the 2SD1071 from China. I purchased a batch that looked genuine but did not work as they were faulty (poor Gain) obviously dodgy. Other batch from China was good.
Debe are the good ones "Fuji Brand"? I have a single cylinder with poor points and a twin that has never sparked. I think I will build thee plus a spare. Is Alloy plate sinking heat? can these be mounted under the flywheel? What are you potting these with?

Matt

Potting ref
http://www.electro-tech-online.com/attachments/module12-jpg.74321/

#### debe

##### Active Member
Fuji brand should be ok, the alloy plate is a heat sink. I used 5Minute Araldite for potting. If you can make it small enough & theres enough room then it can be fited under the flywheel.

#### WisconsinOutboards

##### New Member
Fuji brand should be ok, the alloy plate is a heat sink. I used 5Minute Araldite for potting. If you can make it small enough & theres enough room then it can be fited under the flywheel.
Thanks what is the new component across the leads? Mosorb? Are there two suggestions 1N6303A or 15KE200A seem quite expensive compared to the rest of the items.

Matt

#### debe

The Mosorb is there to clip high voltage spikes. I found some Ign coils would destroy the switching transistor. So its there for reliability, I did not think $2 each was that expensive. #### WisconsinOutboards ##### New Member The Mosorb is there to clip high voltage spikes. I found some Ign coils would destroy the switching transistor. So its there for reliability, I did not think$2 each was that expensive.
Thanks! Originally I could only find them for $10 each or 3 for$29 now I found ten 1N6303A for $9.09 so for$25 I will have enough components to build 10 Red ATOMS and resistors for 90 more. Yes the capacitor in your picture is a box... any reason the round ones cannot be used? Currently I need 3-6 some are fine on points today... but I am sure more old outboards may find me.

Can you provide some x,y,z dimensions of you dead bug circuit in mm with x defined as the long side and z out of the page.

Regards Matt

#### WisconsinOutboards

##### New Member
Ive filled in where the wires go. The polarity is trial & error, if you don't get a good blue spark, wire it up opposite polarity. It will depend entirely what polarity the pulses are from the coil.View attachment 105098

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