AC DC adapter help please

aveatry

aveatry

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Need a new adapter for a DAB radio the one I am replacing is 8.5V 1.53A but confused as it can also run off 4 AA battery's which equal 6V so can I buy any adapter from 6V to 8.5V
Looking at this one on CPC . the polarity is correct and the barrel plug
Output Power Max: 8.4W
Output Voltage - Output 1: 7.5V
Output Current - Output 1: 1.2A
2.5 x 5.5 x 12mm (Female)
Polarity: +ve (positive) centre
Thank you
 
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does it also charge the batteries - we have a couple of roberts radios - which also charge the batteries - 4x 1.5V

I ended up buying direct from roberts
charger is 7.5v and 1.6A and charges the batteries

the output of the one quoted is 7.5v and 1.2A so not a match - it may work - but i would get the same voltage and same or greater current rating
 
Make and model of DAB radio?
Make and model off the (faulty) existing adapter? (A photo could help).
 
No guarantees, but that would probably work just fine - it certainly would not cause any harm. Better/ more likely to work, would be one with a higher current rating.
 
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Thanks everyone its a goodman's GMR86DAB and yes looking properly at the back it does have an option to use rechargeable battery and leave them it to charge - so is that why the adapter is 8.5V.
I don't use the facility so just an AC adapter to run the radio without charging would do.
Also I was assuming it was the adapter causing an issue which is when I turn it on the screen flickers for up to 1 min before the radio switches on and then sometimes randomly does it again while it is on. But if I just use it with normal AA's then it works fine.
IMG_20240422_111608381.jpg
IMG_20240422_111633239.jpg
 
aveatry said:
.... its a goodman's GMR86DAB and yes looking properly at the back it does have an option to use rechargeable battery and leave them it to charge - so is that why the adapter is 8.5V.
Click to expand...
Yes, vey probably - to charge 6V worth of batteries needs more than 6V.

It sounds as if you don't use batteries at all but, if you did, you would need to heed the (red) 'Warning' on the back. If you connected the AC adapter whilst there were non-rechargeable batteries in it, it would attempt to charge those batteries which, in the worst-case scenario, might cause them to 'blow up'.

In practical terms, if there are no batteries in it, I imagine that a 6V adapter would work fine for you.
 
Ok thank you both for your help.
New Update.
I found I have a multi AC Dc adapter with plug in connectors and an adjustable V.
I tried it on 6V and it presented the same flickering before it turned on.
Then I set the adapter to 7.5V and it came straight on without any flickering.
So any ideas what that is telling me. :unsure:
 
aveatry said:
I found I have a multi AC Dc adapter with plug in connectors and an adjustable V. ... I tried it on 6V and it presented the same flickering before it turned on.
Then I set the adapter to 7.5V and it came straight on without any flickering. ... So any ideas what that is telling me. :unsure:
Click to expand...
Thanks for the update. That's rather odd, given that it works fine on 4 x AA batteries, which will provide 6V at most.

The only thing I can think of that your experience may be telling you is that your multi-voltage adapter is not providing at least 6V when set to that voltage and [powering your radio. One thought - what is the current capability of this adapter? - if it is 'low', that might explain why its voltage is (presumably) dropping to below 6V when powering your radio.

Do you have the means to measure the output voltage of the adapter (when running the radio)?

Kind Regards, John
 
JohnW2 said:
Do you have the means to measure the output voltage of the adapter (when running the radio)?

Kind Regards, John
Click to expand...
Yes I have a multimeter but where would I measure from when it its plugged and running the radio in as I can not access the barrel plug.
 
5.96V on no load
It does start on the 6v after a about 30 seconds of flickering.
After it has settled and is working If turn it off at the mains and then back on at the mains it comes on ok - like something first needs to warm up inside the radio
 
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aveatry said:
Yes I have a multimeter but where would I measure from when it its plugged and running the radio in as I can not access the barrel plug.
Click to expand...
Good question. I would imagine that you could probably measure where the internal batteries would (if present) be - measuring between the two 'ends' of the string of four batteries.

However, as been said, it's worth first measuring it off-load (i.e. when not connected to the radio, since it's possible that even off-load the voltrage is lower than it should be. If, in it's 6V mode, it's producing less than 6V when off-load, see what comes out when it's set to produce 7.5V
 
on the 7.5 setting I am getting 7.55V
I can not get anything across the battery springs - charge switch was on
 
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