norman

Hi John It's possible that the dynamic brake is on. Within DCC it is possible to select which functions will be on when operating on analogue. e.g. the sound or lights but also the dynamic brake. If whichever function operates the dynamic brake, sometimes F2 or F4 is selected as on for DC then the loco will not move! because the brake is on. It's a Zimo decoder. How are you with programming?

Received two bracket signals today from Hattons - I'm impressed. They work on DC, AC and even DCC power so well done Dapol for getting it right.

ON the SWD web site downloads Steve describes his method for setting a motor up albeit with V4 - same principles but hell of a faff. I'll stick with Zimo in the future.

I had the same issue with a Dapol class121. Ran OK on DC and with a Zimo non sound decoder. Out of stock on Zimo MX644 so had to go with a ESU v5. Jerky at low speed so tried the auto setting but not better at low speed. Ran OK with BEMF off. After several hours of tuning following the ESU handbook and their suggested settings for different motors I have it not jerkying but when running its not smooth like a Zimo. I also tried Steve Weekes recommended method but not successfully. This has confirmed my first choice of Zimo.

Hi Mopar A rolling road is useful but does not test the dual bogies correctly. On the track the bogies need to be balanced but not so on the rolling road. So please test on a length of track at slow speeds and let us know how it does.

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The head code box outer layer of plastic glass can be removed. Just a blob of black tack and quick pull.

Well I have never noticed these additional steps. Did they fold automatically when the door was opened and closed?

The head code box contains two clear plastic inserts. I removed the outer one with a snatched black tack - applied the transfer to the inside face of the out piece and let it dry before trimming to size and reassembling. Perfect.

Included in my box is an etched brass sheet marked as class 121 door step ???? ???? The last two words I can not read. They look like they should be folded on the eteched lines and fitted under the door - but they are painted green. Any one have any clue?

Congratulations to Dapol. They have learnt lessons from the class 122 and applied them to the 121. I fitted a Zimo decoder and this time there was no need to modify the wiring, all lights worked and with a bit of function remapping I am well pleased. Also, the slow running is certainly better no need to switch off back EMF, runs very smoothly.

As Nigel has pointed out there is a CV to control stay alive, it prevents the loco running longer than you wish it to after an interruption. #153 Limiting driving along without data signal SW version 27.10 and higher 0 – 255 0 In case a vehicle has a capacitor, it continues to drive, even when contact to the tracks is lost. If the capacitor is very big (e.g. GoldCap), the distance after losing contact can be fairly long. This is why CV #153 was introduced; it prevents loco driving along without external power supply. CV #153: time in tenths of seconds (i.e. 0 to 25 sec configurable), after which the vehicle stops after a data signal is not received anymore“.

As has been pointed out to Heljan previously there exists a standard drop test for packaging which is 1 metre on to a concrete floor, it's a good starting point. But I doubt that Heljan do this as it seems they would rather just suck it and see what happens. That policy must cost them a fortune and really puts customers off.

I suspect that the delay to the sound fitted 122s is because of the lighting issue due to the Dapol decoder configuration being different to the Zimo.

As above, I want to make the fan work on a class 33 with DCC which on DC has the fan control on the main board. Earlier models had the fan PCB in the roof - that's what I want. Norman

Newer Heljan Diesels have the fan control module incorporated into the main DC board which is redundant when fitting DCC. Using a Zimo MX699KS in a class 33 and hooking the fan to the 5 volt supply produces a fan that runs fast and makes a considerable noise. So I've dimmed it down to reduce the speed to an acceptable level but it it is still too noisy. The Heljan analogue board with a voltage regulator and a potentiometer produces a far better result with good fairly quite running. Are the separate fan control boards available i.e. the ones that Heljan fitted in the roof in earlier models? Is there another way with a DIY solution to achieve the better result?

I tried the Dapol Imperium 3 unfortunately the Dapol information sheet contains no clues as to what is adjustable and I was so disappointed that I fitted a Zimo MX644C and it worked perfectly. Norman

Choose Zimo for sure, MX696 has sufficient functions.

My Dapol bubble car runs smoothly on analogue DC and on DCC and is a excellent model. I'm just waiting for the release of the class 121 now, they should be available pretty soon.

Charlie There is nothing fundamentally wrong with 2 x 1k resistors - it just means that the LEDs are very slightly dimmed.

Hi Mike Sorry but that's not correct. I have removed the Heljan PCB when fitting a Zimo decoder and the LED lights work perfectly as they are protected by surface mount resistors locally. I am still wondering why the two banks of very small resistors are fitted. They are only about 2 ohms each and they have no effect upon the function outputs I think they must be something to do with radio and TV interference suppression.

No the lights are all LEDs already. I think only the very early Heljan diesels used bulbs.

To fit a decoder you need to remove the Heljan PCB. Do you need to add resistors for the lighting?

Eureka a light bulb moment OK I have set my Zimo636D to become a 636C by writing 3 to CV8 which configures two functions to logic level and now it works perfectly. So exactly as the Dapol booklet (almost) they say F4 for interior whereas its F5.

Using decoderpro and a Zimo decoder I have managed to get the running lights and interior lights sorted but not the cab lights. F0 is one end directional white/red and F1 the other end directional with F5 the interior. So I have ordered a Imperium 3 just to see if I can get all lights to work correctly. According to decoderpro I'm using FO(f) FO(r) FO(1) FO(2) FO(4)