|
Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
|
Thread Tools |
20th Oct 2021, 9:57 pm | #1 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
|
Grundig Yacht Boy 210.
While clearing another house at work today .i came across this .Once home and with its back off you can see the damage done by the old batteries having said that because of the design the damage is limited to the battery compartment. After removing the old batteries i connected a PP9 but the set was dead .Cleaning the bat/mains switch brought the thing to life although the sound is not that good [distorted ] i would like to check the quiescent current but cant for the life of me find the link .can anyone point me in the right direction please
|
20th Oct 2021, 10:30 pm | #2 |
Hexode
Join Date: Oct 2010
Location: Box End, Beds. UK.
Posts: 271
|
Re: grundig yacht boy 210
I would look near the output transistors for what looks like a hand soldered blob of solder on the board - it will be across the two pads
|
20th Oct 2021, 11:06 pm | #3 |
Hexode
Join Date: Aug 2014
Location: Featherstone, West Yorkshire, UK.
Posts: 386
|
Re: grundig yacht boy 210
Just inboard of T10, the bottom output transistor, there are two pads connected to its collector. Break this link and set the quiescent current to 5.5mA with R52.
|
21st Oct 2021, 6:14 am | #4 |
Hexode
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
|
Re: Grundig Yacht Boy 210.
These Grundigs (and many other sets using the same type of output transistors) are starting to suffer from Tin Whisker failure whereby there is leakage from the electrodes to the case of the device. a quick test for this is to disconnect the transistor from the heatsink. If the distortion goes away or is significantly reduced, you have your answer. (I have had 3 Yacht Boys and 4 Hackers with this problem) Of course, check the quiescent current first though as more than a few had it set incorrectly from the factory.
|
21st Oct 2021, 6:41 am | #5 |
Octode
Join Date: Mar 2015
Location: Yorkshire, England.
Posts: 1,294
|
Re: Grundig Yacht Boy 210.
Good ol' reliable Duracell's! Did you check the expiration date?
__________________
Regards, Ken. BVWS member |
21st Oct 2021, 11:58 am | #6 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
|
Re: Grundig Yacht Boy 210.
thanks guys . i didn't check the dates on the batteries just wanted them out .I removed the chassis and then gave the cabinet a good wash in hot soapy water .Once dry i cleaned all of the battery contacts and once fettled up its ready for the chassis to go back in. Oh yes and of course the two small knobs are missing [don't think I've ever seen one with all of its knobs in situ]
|
21st Oct 2021, 1:00 pm | #7 |
Octode
Join Date: Sep 2020
Location: Thetford, Norfolk, UK.
Posts: 1,731
|
Re: Grundig Yacht Boy 210.
|
22nd Oct 2021, 12:23 am | #8 |
Heptode
Join Date: Apr 2016
Location: Cheltenham, Gloucestershire, UK.
Posts: 872
|
Re: Grundig Yacht Boy 210.
The 'expiry' date seems to be academic - they fail whenever it suits them .... usually prematurely!
__________________
Red to red, black to black. Throw the switch and stand well back! |
22nd Oct 2021, 7:04 pm | #9 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
|
Re: Grundig Yacht Boy 210.
does the radio need to be on a station before adjusting anything?
|
22nd Oct 2021, 7:15 pm | #10 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,787
|
Re: Grundig Yacht Boy 210.
No. When adjusting the quiescent current, the volume should be at minimum.
|
23rd Oct 2021, 8:31 pm | #11 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
|
Re: Grundig Yacht Boy 210.
|