Roberts R 505 - UK Vintage Radio Repair and Restoration Discussion Forum

kirstyd · 19th Jan 2021, 7:21 pm

Hi All
This Roberts had a couple of bad capacitors and scratchy pots all now sorted but there seems to be a problem with its speaker ever so slight distortion [I have tried another speaker and its fine with that] i thought at first the problem could have been caused by all the crud and dirt that had managed to work its way through the speaker grill over the years [bit of old digestives and god knows what else] but after cleaning everything and reassembling the radio the distortion is still there .The speaker is a 5 by 3 elliptical 4 ohm .can anyone tell me if its possible to get a replacement or something that would do the job .I have seen a speaker that's the correct size for sale but its 8 ohms would that do ?.I have to say that when connected to a decent size speaker the sound is very good .Shame there isn't room for something bigger

pip5678 · 20th Jan 2021, 11:36 am

I have a Roberts R505 in the to do pile, the AF and speaker work fine but there is an FM tuning fault. PM me if you think you can persuade me into breaking the set up to sell the speaker.

chriswood1900 · 20th Jan 2021, 4:42 pm

Does the existing speaker cone move freely without making a scratching or scrapping noise?
It is also worth trying the speaker the other way up, over time the coil sags and rubs on the magnet, if that doesn't work you will need to use your powers of persuasion on pip5678.
Good luck

kirstyd · 20th Jan 2021, 6:07 pm

since my last post i have dismantled the radio and removed the speaker .When running with the speaker out of the cabinet it seems to be ok .i can only guess that when clamped down in its cabinet the speaker frame is being pulled out of shape .I applied slight pressure to the corners of the speaker while it was on and sure enough it distorted .I think experiments with washers may cure the problem .The speaker is made from little more than tin and can be twisted out of shape easily .At least a solution seem to be in sight. Thanks for your input guys

19th Jan 2021, 7:21 pm	#1
kirstyd Heptode Join Date: Mar 2014 Location: Leeds, West Yorkshire, UK. Posts: 660	Roberts R 505 Hi All This Roberts had a couple of bad capacitors and scratchy pots all now sorted but there seems to be a problem with its speaker ever so slight distortion [I have tried another speaker and its fine with that] i thought at first the problem could have been caused by all the crud and dirt that had managed to work its way through the speaker grill over the years [bit of old digestives and god knows what else] but after cleaning everything and reassembling the radio the distortion is still there .The speaker is a 5 by 3 elliptical 4 ohm .can anyone tell me if its possible to get a replacement or something that would do the job .I have seen a speaker that's the correct size for sale but its 8 ohms would that do ?.I have to say that when connected to a decent size speaker the sound is very good .Shame there isn't room for something bigger Attached Thumbnails

20th Jan 2021, 11:36 am	#2
pip5678 Tetrode Join Date: Jan 2019 Location: Manchester, UK. Posts: 97	Re: roberts R 505 I have a Roberts R505 in the to do pile, the AF and speaker work fine but there is an FM tuning fault. PM me if you think you can persuade me into breaking the set up to sell the speaker.

20th Jan 2021, 4:42 pm	#3
chriswood1900 Octode Join Date: Jan 2007 Location: Bristol, UK. Posts: 1,047	Re: Roberts R 505 Does the existing speaker cone move freely without making a scratching or scrapping noise? It is also worth trying the speaker the other way up, over time the coil sags and rubs on the magnet, if that doesn't work you will need to use your powers of persuasion on pip5678. Good luck __________________ Chris Wood BVWS Member

20th Jan 2021, 6:07 pm	#4
kirstyd Heptode Join Date: Mar 2014 Location: Leeds, West Yorkshire, UK. Posts: 660	Re: Roberts R 505 since my last post i have dismantled the radio and removed the speaker .When running with the speaker out of the cabinet it seems to be ok .i can only guess that when clamped down in its cabinet the speaker frame is being pulled out of shape .I applied slight pressure to the corners of the speaker while it was on and sure enough it distorted .I think experiments with washers may cure the problem .The speaker is made from little more than tin and can be twisted out of shape easily .At least a solution seem to be in sight. Thanks for your input guys