AOR 7030 Power supply - UK Vintage Radio Repair and Restoration Discussion Forum

carlos2008 · 10th Oct 2022, 7:36 pm

Hello,

Recently I have purchased a AOR 7030 receiver at a fair price. It needs some care, there is a faulty push button, no sound comes from the internal speaker, some hex screws are missing and few bits and bobs inside as well.

Regrettably, no external power supply came, the original AOR PSU7030/1, only a 12v switched-mode power supply.

I have decided to make one myself, 15VDC 800 mA linear power supply. Although the manual indicates current 300 to 500mA, 1A max.

I have already built some PS in the past but I have some doubts with this, Would it be enough with a LM7815 voltage regulator some electrolytic capacitors, diodes and a 18VAC output trafo?
I have seen some schemes that use a 2n3055 and a lm7815 together
Do you think that the 2n3055 will be necesary? 7815 can bear to 1amp.

I have another question about replacing the internal battery too.

Any comments and help are greatly appreciated.
Thank you very much in advance.

mervyn · 11th Oct 2022, 9:26 am

I have just replaced the internal battery on one of these.

If you take top cover (which also houses speaker) and rest it without disconnecting from main board.

then located the battery which will be on from control panel but at the top so it has easy access, its the green thing at top

Snip the battery off as close to the battery as possible leaving the two tags left .

Snip a little bit of the new battery legs so it will have same height as origional battery off board

Tin the battery leads and also run a bit of solder on the tags which are still attached to the control board

put one leg on and run soldering iron over it so the leg is soldered then do the other leg.

that's is about it but pay attention to the polarity.

It takes far longer to describe than to do.also doing it this way you do not disturbed the main board

agc settings will be lost (never really bothered me) but filters can be recalibrated from front panel

all should be good

Do this every two years and it should last. they are lovely receivers with excellent audio quality

Merv

jez_145 · 11th Oct 2022, 9:27 am

Hi Carlos and welcome to the forum.

I've attached the AR7030 PSU circuit taken from the official service manual kit - for reference.

I think a regulated supply, based on a 7815, would be fine for this application. The 2N3055 shown in your attached circuit is just there to add greater current handling - which wouldn't be needed in this case.

As for the internal rechargeable cell (1/3 AAA as a remember ?) - I just removed mine and fitted a full size rechargeable AAA in a battery holder inside the AR7030 case and soldered wires between this and the contacts on the PCB where the original cell was placed. This makes it easier to replace in the future and has significantly more capacity than the original cell of course.

Before going to the trouble of building your own supply, etc, I would suggest you make sure you can get the radio working properly first if it has other issues. Good luck!

Jerry

mervyn · 11th Oct 2022, 2:03 pm

FYI

There was a warning from AOR with regards doing the "external" cell due to possible ESD component failure but i understand the benefits of not having to unsolder the cell each time

Merv

carlos2008 · 11th Oct 2022, 4:15 pm

Thanks for the useful advices.

The AOR PS seems more sophisticated than the one I want to build. I see it has a 3 wire output transformer but the VAC output value is not indicated in the scheme.
I think I will go to the one with the 7815 regulator with a good toroidal transformer. It said that the original AOR PS runs hot and has a capacitor that is a must to be replaced.
In this website there is some info about the power supply and more:
https://www.qsl.net/n9ewo/ar7030.html

I was very lucky in getting my 7030 with the filter board and a 2.4 Khz fitted, noise blanker and notch board is also fitted and a K455J 3 Khz filter .

Concerning the battery issue I can not do the 'external' modification because the NB and filter boards are fitted and there is no space.
I already knew about that modification, it is a good idea. It can be seen in this webpage:
https://www.dx.cz/index.php?id=418
And this ebay seller gives some instructions in replacing the battery, parallel:
https://picclick.co.uk/Aor7030-Ar703...960995836.html

I attach a couple of photos, the battery seems that has been previously replaced.
Maybe this night I will test the radio, I hope that everything is correct.
Quite sure that I will write again, this receiver is more complicated that the Lowe HF-150 that I have been using for years.
Regards.

carlos2008 · 17th Oct 2022, 12:11 pm

Since it is quite difficult to find a used original power supply I have found a very good 15v 900 mA PS.
I do not know if will match with the radio, receiver original specifications indicates:
15V from external AC adapter, current 300 to 500mA typical, 1A max. 30mA on standby.

And the original power supply delivers 800 mA, according Universal Radio:
https://www.universal-radio.com/cata...rxvr/0925.html

Should I buy the 900 mA or it would be better one with 1A output?
This is the 900mA PS:

https://www.mouser.es/ProductDetail/...XIb65oGw%3D%3D

Thanks for the help and advices.

10th Oct 2022, 7:36 pm	#1
carlos2008 Triode Join Date: Apr 2008 Location: Zaragoza Spain Posts: 10	AOR 7030 Power supply Hello, Recently I have purchased a AOR 7030 receiver at a fair price. It needs some care, there is a faulty push button, no sound comes from the internal speaker, some hex screws are missing and few bits and bobs inside as well. Regrettably, no external power supply came, the original AOR PSU7030/1, only a 12v switched-mode power supply. I have decided to make one myself, 15VDC 800 mA linear power supply. Although the manual indicates current 300 to 500mA, 1A max. I have already built some PS in the past but I have some doubts with this, Would it be enough with a LM7815 voltage regulator some electrolytic capacitors, diodes and a 18VAC output trafo? I have seen some schemes that use a 2n3055 and a lm7815 together Do you think that the 2n3055 will be necesary? 7815 can bear to 1amp. I have another question about replacing the internal battery too. Any comments and help are greatly appreciated. Thank you very much in advance. Attached Thumbnails

11th Oct 2022, 9:26 am	#2
mervyn Hexode Join Date: Mar 2005 Location: Whitfield, Dover, Kent, UK. Posts: 258	Re: AOR 7030 Power supply I have just replaced the internal battery on one of these. If you take top cover (which also houses speaker) and rest it without disconnecting from main board. then located the battery which will be on from control panel but at the top so it has easy access, its the green thing at top Snip the battery off as close to the battery as possible leaving the two tags left . Snip a little bit of the new battery legs so it will have same height as origional battery off board Tin the battery leads and also run a bit of solder on the tags which are still attached to the control board put one leg on and run soldering iron over it so the leg is soldered then do the other leg. that's is about it but pay attention to the polarity. It takes far longer to describe than to do.also doing it this way you do not disturbed the main board agc settings will be lost (never really bothered me) but filters can be recalibrated from front panel all should be good Do this every two years and it should last. they are lovely receivers with excellent audio quality Merv

11th Oct 2022, 2:03 pm	#4
mervyn Hexode Join Date: Mar 2005 Location: Whitfield, Dover, Kent, UK. Posts: 258	Re: AOR 7030 Power supply FYI There was a warning from AOR with regards doing the "external" cell due to possible ESD component failure but i understand the benefits of not having to unsolder the cell each time Merv

11th Oct 2022, 4:15 pm	#5
carlos2008 Triode Join Date: Apr 2008 Location: Zaragoza Spain Posts: 10	Re: AOR 7030 Power supply Thanks for the useful advices. The AOR PS seems more sophisticated than the one I want to build. I see it has a 3 wire output transformer but the VAC output value is not indicated in the scheme. I think I will go to the one with the 7815 regulator with a good toroidal transformer. It said that the original AOR PS runs hot and has a capacitor that is a must to be replaced. In this website there is some info about the power supply and more: https://www.qsl.net/n9ewo/ar7030.html I was very lucky in getting my 7030 with the filter board and a 2.4 Khz fitted, noise blanker and notch board is also fitted and a K455J 3 Khz filter . Concerning the battery issue I can not do the 'external' modification because the NB and filter boards are fitted and there is no space. I already knew about that modification, it is a good idea. It can be seen in this webpage: https://www.dx.cz/index.php?id=418 And this ebay seller gives some instructions in replacing the battery, parallel: https://picclick.co.uk/Aor7030-Ar703...960995836.html I attach a couple of photos, the battery seems that has been previously replaced. Maybe this night I will test the radio, I hope that everything is correct. Quite sure that I will write again, this receiver is more complicated that the Lowe HF-150 that I have been using for years. Regards. Attached Thumbnails Last edited by carlos2008; 11th Oct 2022 at 4:45 pm. Reason: forgotten photos

17th Oct 2022, 12:11 pm	#6
carlos2008 Triode Join Date: Apr 2008 Location: Zaragoza Spain Posts: 10	Re: AOR 7030 Power supply Since it is quite difficult to find a used original power supply I have found a very good 15v 900 mA PS. I do not know if will match with the radio, receiver original specifications indicates: 15V from external AC adapter, current 300 to 500mA typical, 1A max. 30mA on standby. And the original power supply delivers 800 mA, according Universal Radio: https://www.universal-radio.com/cata...rxvr/0925.html Should I buy the 900 mA or it would be better one with 1A output? This is the 900mA PS: https://www.mouser.es/ProductDetail/...XIb65oGw%3D%3D Thanks for the help and advices.