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12dstring

USB EQDir for under £4

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If they are using 'proper' FTDI chips then this should do what you want http://www.ebay.co.uk/itm/USB-to-TTL-Serial-Cable-Adapter-FTDI-Chipset-FT232-Cable-FT232RL-TTL-3-3V-B36-/231609039965?pt=LH_DefaultDomain_3&hash=item35ecf97c5d , just need to wire up an RJ45 on the end...

for a little more work in 'potting-up' this may be useful http://www.ebay.co.uk/itm/6PIN-CP2102-USB-2-0-to-UART-TTL-Electronic-Connector-Serial-Converter-Module-/390568169609?hash=item5aefad5089

As for drivers for Windows 8,8.1,10, you need to set the OS into 'allow un-signed drivers' mode (special start-up) which will then install correctly & work ok, I have some on multiple systems 

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Seriously, these mounts are upwards of £700, the EQ8 being a few grand.  Purchese a genuine FTDI cable from the manufactures.  I wouldn't (didn't) risk using what can only be cloan chips costing a couple of quid off e-bay.

Drivers up to windows 10 are available http://www.ftdichip.com/FTDrivers.htm

Alternatively, if in doubt, spend £40 - £60 and purchase one of the commercially made EQDirect cables that will have a warranty, and if things go pearshapped you can have some course of redress.  It depends on your confidence.  Personally using genuine FTDI chips I have no worries with the DIY cable I made and use with my HEQ5, which has been fine for the passed three years

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Be careful with ebay sellers as they sell 'FTDI based USB to TTL'

I wrote to FTDI and got his answer:

---------------------------------------------------------------------------------------------------------------------------------------------------------------------
However, to guarantee genuine parts, purchase via our Web Shop and Sales Network including our Global Suppliers

I strongly advise not to order our products on eBay.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------

So I wanted to know what would be wrong with those 'chinese chips' and stumbled upon this (take the time to take a look)

And there are consequences to buying fake chips

The genuine ones are not that much more expensive ;)

Edited by Vox45

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I can't find any reference to an SW EQ5, will this cable work?

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Seriously, these mounts are upwards of £700, the EQ8 being a few grand.  Purchese a genuine FTDI cable from the manufactures.  I wouldn't (didn't) risk using what can only be cloan chips costing a couple of quid off e-bay.

Drivers up to windows 10 are available http://www.ftdichip.com/FTDrivers.htm

Alternatively, if in doubt, spend £40 - £60 and purchase one of the commercially made EQDirect cables that will have a warranty, and if things go pearshapped you can have some course of redress.  It depends on your confidence.  Personally using genuine FTDI chips I have no worries with the DIY cable I made and use with my HEQ5, which has been fine for the passed three years

true, i'm more inclined to use 'quality' parts too, but isn't that just perpetuating the overpricing of a great deal of kit that has 'astro' associated to it.

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true, i'm more inclined to use 'quality' parts too, but isn't that just perpetuating the overpricing of a great deal of kit that has 'astro' associated to it.

I think it's in relation to what that part is.  Buying a cheap eyepiece will still give you a view of a target same as an expensive one.  OK the expensive one will give you a better view, but neither will pose the risk of damage to the scope. However the price difference has a factor into what item you get.  A genuine FTDI cable can be had for £10, whilst the cheap far eastern cloans are just a few quid.  For the sake of the few quid difference it's well worth getting a geniune part.

It's nice to see that HitecAstro have reduced their prices on such cables.  They used to be £40 - £60, now they are a more realistic £28, but then again they use the prolific chip and not an FTDI, which has been know in the past to have issues with driver compatibility.  Astronomiser uses FTDI, and have products competivley priced http://www.astronomiser.co.uk/eqdir.htm and state

Astronomiser has now stopped production of EQ Direct cables using the Prolific chipset - we have decided to focus on the FTDI type which work with all flavours of Windows.

If you really want to save money, but use a genine part that you know won't brick the mount - yes, using cheap cloans can result in the product it is used with becoming a non functional door stop ! - then purchase a cable direct from FTDI for £16 and an RJ45 plug (or network cable) and you'll have an EQDirect cable for less than £20.

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I can't find any reference to an SW EQ5, will this cable work?

Yes the EQDirect cable that suits the HEQ5 will work with the EQ5

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Nice find..   I personally prefer not to rely on a mechanical connection, but for those who want a quick way of making an EQDirect cable, that's a great suggestion

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Nice find..   I personally prefer not to rely on a mechanical connection, but for those who want a quick way of making an EQDirect cable, that's a great suggestion

just bought one... still gonna solder it though :D

have to retain my rep as the demon soldered of olde manchester town...

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you may find that soldering the connection will limit the life of the connector, as the whole point of insulation displacement connectors (IDC) are that they fuse the two metal components together, but adding substances like flux & heat breaks this bond, resulting in lower life\failure.

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there's this one http://www.ebay.co.uk/itm/2pcs-PL2303-PL2303HX-USB-to-TTL-RS232-USB-Serial-Cable-Connector-Adapter-/261110516124?hash=item3ccb66499c only thing to worry about is the listing says it's not compatible with windows 8. wonder if that rules out windows 10 as the free upgrade is out in a few days. I use XP but y'know, others might have trouble.

Thanks Dave-D, much appreciated.

In the end I bit the bullet a bought a pukka Hitecastro unit - all those posts of dire consequences to my shiny new EQ8 got me rattled! :-)

Clear skies!

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I bought the requred chip with a bare wire end and then used an RJ45 connector and crimped the wires according to the EQmode website.

http://eq-mod.sourceforge.net/reqindex.html

When cheking the voltage using pin 4 (GND) and 5 (RXD) I get 4.98v but when I check on the pin 4 and 6 (TXD) it reads around 3.5v

Is this normal ? should I get around 5v on both wires ?

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I bought the requred chip with a bare wire end and then used an RJ45 connector and crimped the wires according to the EQmode website.

http://eq-mod.sourceforge.net/reqindex.html

When cheking the voltage using pin 4 (GND) and 5 (RXD) I get 4.98v but when I check on the pin 4 and 6 (TXD) it reads around 3.5v

Is this normal ? should I get around 5v on both wires ?

At a guess I'd say you're getting 4.98V data back from the mount on RXD, but the chip you have bought is only putting out 3.5V data to the mount on TXD.

According to the EQMod website, the EQ6Pro, HEQ5 type mounts will only work with 5V, the AZ-EQ6GT and EQ8 mounts have a 5V tolerant 3.3V signaling interface.

Michael

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Maybe I am doing my test wrong ! I just plug the USB cable and use a voltmeter on the RJ45 side, I do not plug the cable into the mount (not an electrical genius here ;)

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Does the cable work?

If yes, I wouldn't worry what the unplugged state is.

I would worry if TXD was, say, 12V

Michael

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The PL2303HX chipset has 3.3v TTL level I/O, not 5v.  Some pins are pulled high to the 5v USB lines via internal pull-ups, which might explain why you are getting different voltage levels on different pins, although if it is connecte dto the mount, you will get nearly 5v on RX line as the mount will be sending TTL signals at 5v levels.

The EQMOD site recommends using FTDI chipset at 5v TTL levels, and whilst these may well be 10x the price of the e-bay listing direct from FTDI, they work well and are well supported by FTDI if you ever experience an issue. Spending £15 on a decent cable is nothing when you have a mount costing £700 or more, and I personally wouldn't risk damage to the motor board by using something from HK at less than a quid.

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Does the cable work?

If yes, I wouldn't worry what the unplugged state is.

I would worry if TXD was, say, 12V

Michael

Ok I see what you mean ! thanks

The chip I bought is a 5v chip, I made sure of that. I agree with what other are saying about buying cheap copies from china.

In my case it was more for a POC and I will buy a genuine FTDI one later. It is quite easy if you have the tools to crimp an RJ45 to a wire ended chip (rather than soldering)

Edited by Vox45

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I just  had a senior moment there ...

When I said that when cheking the voltage using pin 4 (GND) and 5 (RXD) I get 4.98v but when I check on the pin 4 and 6 (TXD) it reads around 3.5v

It was actually the opposite... I get 5v on pin 4 and 6 (TXD) and 3.5v on 4 and 5 (RXD) which is the correct voltage for a HEQ5 mount on TXD...

Still no luck, I get connection errors in EQMOD and went through the usual suspect (com port, drivers, reboot, etc) I even change computer from a win7 x32 to a win7 x64 so...

I'll check the wiring and hopefully it is not the FTDI driver refusing to talk to a fake chip :embarassed: although FTDI did say that they would not do that (anymore)

Edited by Vox45

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last update ... gave up ...

Everything that could go wrong did go wrong...

- Ordered from eBay (china) on june 27th... finally got the chip 6 weeks later

- followed EQMOD colors for the RJ45 and like the big dope that I am did not realise that the wire I had did not match the color specifications ... I confused the red for the "orange" (TXD) and used the yellow and black as specified.

Problem is, I did not check the specs for the one I got on eBay... in doubt I went back to the vendor site and saw this:

Red wire: 5V
Black wire: GND
White wire: RXD
Green wire: TXD
Yellow wire: RTS
Blue wire: CTS

I should have gone with Black/White/Green instead of Black/Yellow/red (that I mistooke for the orange) Basically the 1st wire I made was GND/RTS/5v ... Doh! hopefully I did not damage anything by putting 5v on TXD ..

- and finally, as everything was getting very confusing, I opened the USB connector to look at the PCB and, surprise surprise ... Green wire was loose !

post-39102-0-04058300-1442015524_thumb.j

To think that I bought this because I did not want to do soldering on an FTDI chip...

Frankly, all this to save 20£ and it is still not connecting to the mount. I give up, I'll be ordering a genuine chip from FTDI tomorrow ;)

lesson learned.

Edited by Vox45

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There is also a large blob of solder on the pins of the chip itself, which looks like it's shorting a couple of pins, so you may of been stuffed before you even unpacked the thing from the jiffy bag !

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Sometimes the old adage "Buy cheap, buy twice" applies. ☺

There is also a large blob of solder on the pins of the chip itself, which looks like it's shorting a couple of pins, so you may of been stuffed before you even unpacked the thing from the jiffy bag !

Soldering was really awful, I was shocked when I opened the casing... I agree Zakalwe, you get what yo pay for...

I went to the FTDI site to order the chip... The chip is 14.88£ and shipping is 16.93£ for France. Grand total of 36£ ... Might as well buy one from FLO, to support their business and i'd get better customer service if something goes wrong.

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