Which power supply for Grundig Yacht boy 300?
 

Hi everybody,

I have recently acquired a Grundig Yacht Boy 300 at a local flee market. The unit is working perfectly on batteries, but there was no PSU included.

I would like to buy a suitable PSU for it, but do not know exactly which one it needs. Can anybody help?

It only says '7.5 V' on the device where you put the plug, and there is a round whole with a pin in the center. The exact model number is:

GRUNDIG YACHT BOY 300
Z.NR. 7.50027
(It also says 'BATT. 5x1.5V FTZ NR. U 101'. below).

Thanks in advance for your time,

Tim

Re: Which power supply for Grundig Yacht boy 300?
 

7.5V sounds a safe bet from a mains PSU.

PS Welcome to our forum,I should have said first.

Re: Which power supply for Grundig Yacht boy 300?
 

You can get "generic" power supplies with a selectable voltage output and a selection of plug tips to fit various appliances. A transistor radio should not need more than 300mA (but a higher-rated one will not do any harm). Watch the polarity, though. A lot of older kit had the centre pin as negative, although the more common standard today is for the centre pin to be positive. If in doubt, check for continuity between the centre pin of the input socket and each battery terminal.

Re: Which power supply for Grundig Yacht boy 300?
 

the 300B has a centre negative so its presumably, though not necessarily the case for the 300. This model uses 4.5 volts however. I agree with the suggestion of buying a multi power supply I have one running my dab radio and it has been fine.

Re: Which power supply for Grundig Yacht boy 300?
 

The schematic, which is available on this site, tells me that the centre pin is positive and requires 7.5 volts. I see that a Sangean DAB Radio 7.5 volt power supply, which has the right polarity plug, costs £9 from a well known source. What I can't tell is if the plug diameter is correct. A little work at your end will solve the question.

Chris nee Simpsons

Re: Which power supply for Grundig Yacht boy 300?
 

Thanks heaps guys! I will check it, order a PSU and let you know how it worked out.

Re: Which power supply for Grundig Yacht boy 300?
 

... by the way, just check that the PSU provides a Regulated output. That is, on no load (nothing connected to it) the voltage is still 7.5 Volts. There was a range of PSUs sold that provided an unregulated output. For these the 7.5 Volt setting, on a small load like a transistor radio, could well be 12 or more Volts. Such a voltage would damage your radio.

Re: Which power supply for Grundig Yacht boy 300?
 

Might it be possible to get the correct Grundig supply on Ebay perhaps?

Re: Which power supply for Grundig Yacht boy 300?
 

I have noticed this with a couple of AC adapters I own, I didn't know the specifics behind it though.

Re: Which power supply for Grundig Yacht boy 300?
 

Hi, just wanted to report back here.

I bought a multi power supply with positive center pin that has a perfect adapter for the YB300, but it does nothing when attached to it. Maybe it is partly broken and runs only on batteries -- this may even be the reason why they didn't include the power supply on the flea market.

So thanks for all your suggestions, but it looks like I will have to keep running it on batteries. I bought some rechargeable batteries (already have and need tons anyway for flash photography in the studio) and now use it with them.

@HamishBoxer
I already tried getting the correct supply on Ebay, but was not lucky. There were power supplies for many different Grundig models, many for the Yacht Boy 400 for example, but none for the 300 when I checked a few weeks ago.

Re: Which power supply for Grundig Yacht boy 300?
 

You don't always need to buy expensive batteries. You can run multiples of AA 1.5V batteries (in this case just 5 cells) using an adpator to give you your 7.5 volts.

Re: Which power supply for Grundig Yacht boy 300?
 

The type of socket fitted to your Grundig incorporates a Battery/Mains Changeover switch, operated by inserting the DC output plug of your power supply into the socket. The changeover switch could be faulty, and/or possibly have been bypassed so that the radio will only run on batteries.