Philips 13RL360 - UK Vintage Radio Repair and Restoration Discussion Forum

Avid_Nerdlinger · 3rd Oct 2020, 6:55 pm

Got a Philips 13RL360 (£7.22 delivered) from a one time forum member:

https://www.vintage-radio.net/forum/...ad.php?t=95122

I'm guessing it was in storage for the last 7 years, same quietness. This is a radio of substance! I look forward to further exploration, I've already started on the woodwork, gluing. Some suspect-leaky-looking electrolytics and 3 usual suspect AF117s, see photo.

Avid_Nerdlinger · 4th Oct 2020, 5:07 pm

Early success - measured the electrolytics in circuit and they are all low, some practically open including the 32uF (measures about 1uF) one in the AGC feedback path, I soldered a 33uF across it and got BBC Scotland. The waveband switch and volume pot need a clean, some of the other electrolytics need replacing, it needs a general clean and polish and I've a bit more wood glue and clamping to do, otherwise, result!

I'm still quite new to repairing old radios. Any reason I shouldn't just solder a fresh cap across the old dried up one and leave the old one effectively in parallel and making a small but diminishing contribution to the capacitance? I'm thinking it's a way of keeping the history honest, not just being lazy...

G1RAO keith · 4th Oct 2020, 7:41 pm

Hi.

Although it's a quick check for low or o/c caps it is better to replace the faulty component ,because the faulty one could also be leaky ie it is acting like a cap with a resistor across it and for something in the agc line it is just reducing the effectiveness, and any faulty cap between stages will upset the bias. If you ever work on a vintage valve radio leaving leaky caps in cct is a really bad idea. Hope this helps.

Regards, Keith.

Avid_Nerdlinger · 8th Oct 2020, 4:10 pm

Thanks Keith. I've left them in for now though.

I added a couple more electrolytics as required, gave it a good clean, took the sheet metal off the plastic front and glued it back on properly etc. This is my new favourite radio, it has very clear reception of BBC Scotland and 5Live on MW which is unusual here in my experience and it functions a little differently from my other radios - when tuning in and out there is a whooshing sound ( https://youtu.be/U45rK67k5vg ) - I don't know if all this is down to me leaving faulty caps in or other component quality or some aspect of the circuit design which I wouldn't notice if it slapped my head with a fish. Maybe it's not so unusual. Could be to do with the "station focus" fine tuning via a pot and diode as mentioned in Radio and Television Servicing:

"Capacitance Diode Tuning

A number of receivers incorporate bandspread tuning. Control is effected
by means of a potentiometer connected to a reverse-biased diode in the local
oscillator circuit. The small capacitance swing introduced by the diode
limits the range of the oscillator fine tuning and only becomes effective at the
high frequency end of the Medium Waveband. Such a circuit is featured
in Philips models and is termed " Fine Focus " tuning. In this the diode
rectifies the oscillator voltage appearing across the tuned circuit and the
inverse voltage at the anode is set by the potentiometer tuning control (See
Philips model 13RL360 in this volume). "

Avid_Nerdlinger · 20th Oct 2020, 2:53 pm

Inordinately pleased to say this radio is back with shmccall now. I like a happy ending.

3rd Oct 2020, 6:55 pm	#1
Avid_Nerdlinger Pentode Join Date: Apr 2019 Location: Durness, Sutherland, UK. Posts: 108	Philips 13RL360 Got a Philips 13RL360 (£7.22 delivered) from a one time forum member: https://www.vintage-radio.net/forum/...ad.php?t=95122 I'm guessing it was in storage for the last 7 years, same quietness. This is a radio of substance! I look forward to further exploration, I've already started on the woodwork, gluing. Some suspect-leaky-looking electrolytics and 3 usual suspect AF117s, see photo. Attached Thumbnails

4th Oct 2020, 5:07 pm	#2
Avid_Nerdlinger Pentode Join Date: Apr 2019 Location: Durness, Sutherland, UK. Posts: 108	Re: Philips 13RL360 Early success - measured the electrolytics in circuit and they are all low, some practically open including the 32uF (measures about 1uF) one in the AGC feedback path, I soldered a 33uF across it and got BBC Scotland. The waveband switch and volume pot need a clean, some of the other electrolytics need replacing, it needs a general clean and polish and I've a bit more wood glue and clamping to do, otherwise, result! I'm still quite new to repairing old radios. Any reason I shouldn't just solder a fresh cap across the old dried up one and leave the old one effectively in parallel and making a small but diminishing contribution to the capacitance? I'm thinking it's a way of keeping the history honest, not just being lazy... Attached Thumbnails

4th Oct 2020, 7:41 pm	#3
G1RAO keith Pentode Join Date: Mar 2008 Location: Bury, Lancashire, UK. Posts: 138	Re: Philips 13RL360 Hi. Although it's a quick check for low or o/c caps it is better to replace the faulty component ,because the faulty one could also be leaky ie it is acting like a cap with a resistor across it and for something in the agc line it is just reducing the effectiveness, and any faulty cap between stages will upset the bias. If you ever work on a vintage valve radio leaving leaky caps in cct is a really bad idea. Hope this helps. Regards, Keith.

8th Oct 2020, 4:10 pm	#4
Avid_Nerdlinger Pentode Join Date: Apr 2019 Location: Durness, Sutherland, UK. Posts: 108	Re: Philips 13RL360 Thanks Keith. I've left them in for now though. I added a couple more electrolytics as required, gave it a good clean, took the sheet metal off the plastic front and glued it back on properly etc. This is my new favourite radio, it has very clear reception of BBC Scotland and 5Live on MW which is unusual here in my experience and it functions a little differently from my other radios - when tuning in and out there is a whooshing sound ( https://youtu.be/U45rK67k5vg ) - I don't know if all this is down to me leaving faulty caps in or other component quality or some aspect of the circuit design which I wouldn't notice if it slapped my head with a fish. Maybe it's not so unusual. Could be to do with the "station focus" fine tuning via a pot and diode as mentioned in Radio and Television Servicing: "Capacitance Diode Tuning A number of receivers incorporate bandspread tuning. Control is effected by means of a potentiometer connected to a reverse-biased diode in the local oscillator circuit. The small capacitance swing introduced by the diode limits the range of the oscillator fine tuning and only becomes effective at the high frequency end of the Medium Waveband. Such a circuit is featured in Philips models and is termed " Fine Focus " tuning. In this the diode rectifies the oscillator voltage appearing across the tuned circuit and the inverse voltage at the anode is set by the potentiometer tuning control (See Philips model 13RL360 in this volume). " Attached Thumbnails

20th Oct 2020, 2:53 pm	#5
Avid_Nerdlinger Pentode Join Date: Apr 2019 Location: Durness, Sutherland, UK. Posts: 108	Re: Philips 13RL360 Inordinately pleased to say this radio is back with shmccall now. I like a happy ending.