How stupid can I be?

[Geoff S]

2 hours ago, Tom Gaskin 1 said:

If I recall, Futaba are the only RC firm to use that polarity on their chargers, all others use the JR orientation.

 

Tom

 

I'm pretty sure my Frsky transmitter charge inputs have a positive centre orientation.  I remove the batteries in my Taranis to charge because it's easy to do but I use the supplied charger for my Horus because removing the battery means opening the case (6 screws IIRC).  Which reminds me, I have to replace the RTC battery again - they only last about 2 years and are a pain to replace.

[Paul De Tourtoulon]

I never sold JR radios, but if my memory is correct everything I sold had the + in the centre like Futaba, it doesn't really matter if the owners actually read the instructions before turning heir radios on, it would avoid that Magic smoke moment.

[Jim Hearnden 1]

20 hours ago, Geoff S said:

 

I'm pretty sure my Frsky transmitter charge inputs have a positive centre orientation.  I remove the batteries in my Taranis to charge because it's easy to do but I use the supplied charger for my Horus because removing the battery means opening the case (6 screws IIRC).  Which reminds me, I have to replace the RTC battery again - they only last about 2 years and are a pain to replace.

My Code/Etronix/Schumacher 3 channel sets I use for the boats are centre positive as well. I have put rechargables in at least one which means floating about is a centre pos charger..... Danger, Danger....

[Jim Hearnden 1]

Oh well new JR DSM 9 arrived today, it powers on OK, will bind it to the Vapor later. 

[Engine Doctor]

19 hours ago, Jim Hearnden 1 said:

Oh well new JR DSM 9 arrived today, it powers on OK, will bind it to the Vapor later. 

Dont take any chances Jim . Take battery out to recharge .

[Jim Hearnden 1]

Yes its been bound to the Vapor ready for tomorrow. Now on a proper JR charger for tonight. The other one is on its way to Mike Ridley for repair/last rites whatever. 

Not sure what the bill will be for the 9303. But I regard it as stupidity tax on me anyway. 

 

Its been a while since I last flew, so we'll see if thumb memory is a thing.

[Jim Hearnden 1]

Well brilliant service from Mike Ridley. Posted out RM signed for on Saturday to Mike. He emailed me at around 15:30 today to say yes it was just the fuse, all checked over & tested & ready to be posted out to me. After the smell I am amazed that it was just the fuse, it deffo smelt smoky & cremated. Now paid for so will be back with me shortly.

So fantastic service & I can only think I've been very lucky. I now need to decide what to do as I have a 35MHZ 3810 which is OK, a dead 347 which needs new NiMh & CMOS battery. A DSX9 & a 9303 both on 2.4Ghz. In models I have some 35MHZ Rx's a mix of JR & GWS. I have bought a few 2.4GHZ Rx's as well. 

 

PS Flying indoor at Medway was good yesterday. Ended up with two midairs and the second one melted the motor mount so stopped play. The Night Vapor is good fun. I've ordered spares for it x 2 or 3, so I can scratch build a model or two for indoor flying when indoor restarts.

I've been pulling plans from OZ so a lot of choices, also have couple of VMC kits coming. One of which is a Veron Tomtit remake, so will it be rubber/CO2 or electric R/C Hmm....

 

[Jason Channing]

Be careful with the TX as its a USA version and the insurance is not valid using it in the UK, should something happen. I used one till i found out the power output is 1 watt and invalidated my insurance. And thus sold it .

[Jim Hearnden 1]

1 minute ago, Jason Channing said:

Be careful with the TX as its a USA version and the insurance is not valid using it in the UK, should something happen. I used one till i found out the power output is 1 watt and invalidated my insurance. And thus sold it .

I actually asked Mike this directly, as they have the same approval stamps on the back. His exact words " According to my test equipment the output of the 9303 is exactly the same as the DSX9". SO not sure where this has come from but it doesn't appear to be true! I bought the 9303 s/h in the UK but from an area where it may have belonged to an American serviceman originally. 

Putting my radio tech hat on, I would think that although the American 2.4GHZ rules permit more output, they may not use that as it would consume more battery power & therefore shorten flying time. 

But I will investigate more.

[Jason Channing]

30 minutes ago, Jim Hearnden 1 said:

I actually asked Mike this directly, as they have the same approval stamps on the back. His exact words " According to my test equipment the output of the 9303 is exactly the same as the DSX9". SO not sure where this has come from but it doesn't appear to be true! I bought the 9303 s/h in the UK but from an area where it may have belonged to an American serviceman originally. 

Putting my radio tech hat on, I would think that although the American 2.4GHZ rules permit more output, they may not use that as it would consume more battery power & therefore shorten flying time. 

But I will investigate more.

Google 9303,and the other unofficial distributor of JR at the time (not McGregor) the DSX9 is the UK model which has a different power board and has the CE mark

Edited February 19 by Jason Channing

[Martin Harris - Moderator]

A check with the BMFA may confirm this opinion - I'm not sure that using a non-compliant radio automatically invalidates your insurance, especially if there's no element of the radio's output being contributory to an incident but I'm not an insurance expert.

 

In the meantime, if your radio's history/age is unknown, this might be of interest:

https://www.modelflying.co.uk/service-annoucement-made/

[Piers Bowlan]

12 hours ago, Jim Hearnden 1 said:

I actually asked Mike this directly, as they have the same approval stamps on the back. His exact words " According to my test equipment the output of the 9303 is exactly the same as the DSX9". SO not sure where this has come from but it doesn't appear to be true! I bought the 9303 s/h in the UK but from an area where it may have belonged to an American serviceman originally. 

Putting my radio tech hat on, I would think that although the American 2.4GHZ rules permit more output, they may not use that as it would consume more battery power & therefore shorten flying time. 

But I will investigate more.

My JR9303 manual states the output is 750mW. The European (UK) max is 100mW. I believe this equates to a 2 to 3db difference in the power at the aerial as it is not a linear relationship but correct me if I am wrong.

My JR 9303 transmitter was made in Japan although bought in the US. Strangely it has a CE mark on the back along with FCC for the US. I don’t know what the Tx power output limit is in Japan. I have used it for slope soaring in the US, UK, Japan and South Africa. Nowadays I tend to just use my XG11 in the UK.

Both Txs have always worked perfectly and Ouse quality, shame they are not made any more.

Edited February 20 by Piers Bowlan

[Jim Hearnden 1]

10 hours ago, Martin Harris - Moderator said:

A check with the BMFA may confirm this opinion - I'm not sure that using a non-compliant radio automatically invalidates your insurance, especially if there's no element of the radio's output being contributory to an incident but I'm not an insurance expert.

 

In the meantime, if your radio's history/age is unknown, this might be of interest:

https://www.modelflying.co.uk/service-annoucement-made/

Yes aware of that one thanks. That was one of the reasons I sent it to Mike. I assume he'll have checked that.

[John Lee]

I seem to recall that Probuild-UK imported & sold those JR 9303 radios in about 2010-2012. They stated that they were imported directly from Japan, not via the USA, and were to UK specs. I looked at them at the time but in the end bought a McGregor imported DSX9 to replace my PCM9X.

[Jim Hearnden 1]

1 hour ago, Piers Bowlan said:

My JR9303 manual states the output is 750mW. The European (UK) max is 100mW. I believe this equates to a 2 to 3db difference in the power at the aerial as it is not a linear relationship but correct me if I am wrong.

My JR 9303 transmitter was made in Japan although bought in the US. Strangely it has a CE mark on the back along with FCC for the US. I don’t know what the Tx power output limit is in Japan. I have used it for slope soaring in the US, UK, Japan and South Africa. Nowadays I tend to just use my XG11 in the UK.

Both Txs have always worked perfectly and Ouse quality, shame they are not made any more.

Just checked my manual & it doesn't state power output! BUT it does state max power draw as 70mA. Which means overall draw at say 10V is 0.7Watts, so given that its impossible for it to radiate 0.75Watts. 

This ties back to what I said previously, guessing the CPU & other electronics use around 40ma, then the remainder is Tx output. at 10V that is 0.3Watts assuming the 70ma power draw. If it was 750mW as people are saying then that will be 0.75A or 750mA JUST for the RF. That would give a total draw of 0.79Amps or 790mA. With a 1500mAH NiCd that would be around 2 hours flying, which seems to be very low. 

I left mine on to do a discharge test & on a newish pack, fully charged it ran for around 5 hours on a 2400mAH pack. That points to a draw of around 480mAH assuming I've used all the pack which I didn't. 

So also using Mike Ridleys comment that the output is identical to a DSX9 and he sees lots of them so should know then I believe that there is some dodgy info floating around here. 

Someone on RC groups who apparently was the designer of the Spektrum said there are two output boards, but working globally I wonder if that is power or approvals (which may or may not include power output)? Having dealt with EU vs USA (UL) approvals in my day job I know they are very often different just to obscure/confuse be a PITA in the market.  MacGregor doing some market protection maybe?

I love the whole JR thing, starting from my X347 which was around 32 years ago 

[Jim Hearnden 1]

2 minutes ago, John Lee said:

I seem to recall that Probuild-UK imported & sold those JR 9303 radios in about 2010-2012. They stated that they were imported directly from Japan, not via the USA, and were to UK specs. I looked at them at the time but in the end bought a McGregor imported DSX9 to replace my PCM9X.

That makes sense, the label on the back of the 9303 is IDENTICAL to the DSX9! 

[Jason Channing]

1 hour ago, Jim Hearnden 1 said:

That makes sense, the label on the back of the 9303 is IDENTICAL to the DSX9! 

Another company xxxxxx bought in the 9303 which is an American version and not a European version and the software was American with American power outputs, the 9303 was never modified for European use , Very confident that the throttle on your radio is analogue where as the European  DSX 9 is digital so straight away one of the main boards is different,

 

 

Edited February 20 by Jason Channing

[Jim Hearnden 1]

1 minute ago, Jason Channing said:

Another company xxxxxx bought in the 9303 which is an American version and not a European version and the software was American with American power outputs, the 9303 was never modified for European use , Very confident that the throttle is analogue where as the DSX 9 is digital so straight away one of the main boards is different,

 

 

Throttle trim is electronic on the DSX9 but mechanical on the 9303 apparently.

[Jason Channing]

1 minute ago, Jim Hearnden 1 said:

Throttle trim is electronic on the DSX9 but mechanical on the 9303 apparently.

I just said that, the same as the slow blow fuse would be the  problem.

[Jim Hearnden 1]

Just answered the door to the postie, for box with 9303 back. Fantastic turnaround by Mike. would recommend him.