Crystalling Pye PF85's. - UK Vintage Radio Repair and Restoration Discussion Forum

HMV 1120 · 20th Sep 2012, 3:08 pm

Does anyone know the formula for the receive crystals in Pye (Philips) PF85 PMR sets? I have a pair of marine vhf sets arriving soon (Band A1 or B2), each set up on marine channel 69. I'd like to move them up to 162.025 mhz and take off a tap at the discriminator for decoding maritime AIS data.

Many thanks and kind regards,

Robert B.

Steve_P · 20th Sep 2012, 5:28 pm

This might help. When you get them, look at what sort they are and then come back if needed.

http://home.wanadoo.nl/pmpc/PFX_Series.htm

Cheers,

Steve P.

davidw · 20th Sep 2012, 7:31 pm

Robert,according to Chris Loreks PMR Conversion book PF85 A1 and B2 sets receive crystal is :-
Crystal Freq= (receive freq-10.7 Mhz)/3 so thats (162.025-10.7)/3 = 50.4417Mhz.
Hope that helps.

kernowcam · 20th Sep 2012, 8:16 pm

I would ring Quartslab to ask and order from. They are pretty good at this sort of thing.

G6Tanuki · 20th Sep 2012, 8:27 pm

Despite a 30-year history of recrystalling numerous Pye Cambridges/Vanguards/Westminsters/Whitehalls/Europas onto 144MHz, and having also earned my living for half-a-decade installing the Pye "MOULD" Pegasus-type radios, these days to be honest it just doesn't make sense to bother with rock-bound surplus PMR gear.

A couple of crystals cut to your intended frequency will probably cost more than a 'budget' chinese frequency-synthesized transceiver from the likes of wouxon or Feidaxin.

G8UWM-MildMartin · 20th Sep 2012, 11:38 pm

Or even a Baofeng for £30 or less.
But it is economically viable, for receive only, on one channel on two identical high-quality ex-PMR units, which I think was what Robert B. was intending?

HMV 1120 · 21st Sep 2012, 11:00 am

Indeed, there are two AIS frequencies on which vessels transmit identity and position data, and being in Falmouth I thought I'd give it a go. I've tried taking the audio output from a synthesised RX to my soundcard for decoding, but this is resulting in a high percentage of errors. For packet data work a discriminator tap is more reliable, and I don't wish to modify this rig (or tie it up on AIS when it's often used as a general 2 meters monitor).

It also helps that I already have a PFX and PF85 on 70cms and a charger to accompany them, so a new pair of batteries are worth the £5 each they cost me. Getting a pair of crystals cut will be less than the cost of buying a new receiver (and potentially wrecking it trying to tap the discriminator) and far less than even a "budget" professional AIS decoder (prices start around £100).

Many thanks for the crystal data, I shall report back as this proceeds.

Regards,

Rob

HMV 1120 · 29th Sep 2012, 9:38 pm

Further to the above, the sets have arrived and both appear to be in good shape. The batteries are recent replacements and hold their charge well, which is a nice bonus.

One shall be crystalled for AIS reception here. The other I should like to crystal for channel 16 under my portable marine licence. I assume the transmit frequency for these is F/9, i.e. for 156.8 = 17.4222. I'd be greatful if this could be confirmed.

My thanks and kind regards,

Robs

davidw · 30th Sep 2012, 8:32 am

Not quite Rob, according to the same source as post#3 the A1 and B2 transmit is f/8 (the uhf versions are f/9) so for 156.8, Xf= 156.8/8=19.6Mhz.
Both Chris Lorek's books are a must if you are into modifying ex PMR stuff. (no connection just a satisfied user)

Biggles · 5th Oct 2012, 10:19 pm

I think I've got a PF85 service manual lurking about somewhere if you need more info.
Alan.

20th Sep 2012, 3:08 pm	#1
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Crystalling Pye PF85's. Does anyone know the formula for the receive crystals in Pye (Philips) PF85 PMR sets? I have a pair of marine vhf sets arriving soon (Band A1 or B2), each set up on marine channel 69. I'd like to move them up to 162.025 mhz and take off a tap at the discriminator for decoding maritime AIS data. Many thanks and kind regards, Robert B. __________________ Real radios glow in the dark M6GLD

20th Sep 2012, 5:28 pm	#2
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Crystalling Pye PF85's. This might help. When you get them, look at what sort they are and then come back if needed. http://home.wanadoo.nl/pmpc/PFX_Series.htm Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

20th Sep 2012, 8:16 pm	#4
kernowcam Pentode Join Date: Dec 2011 Location: Camelford, Cornwall, UK. Posts: 188	Re: Crystalling Pye PF85's. I would ring Quartslab to ask and order from. They are pretty good at this sort of thing.

20th Sep 2012, 8:27 pm	#5
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,010	Re: Crystalling Pye PF85's. Despite a 30-year history of recrystalling numerous Pye Cambridges/Vanguards/Westminsters/Whitehalls/Europas onto 144MHz, and having also earned my living for half-a-decade installing the Pye "MOULD" Pegasus-type radios, these days to be honest it just doesn't make sense to bother with rock-bound surplus PMR gear. A couple of crystals cut to your intended frequency will probably cost more than a 'budget' chinese frequency-synthesized transceiver from the likes of wouxon or Feidaxin.

20th Sep 2012, 11:38 pm	#6
G8UWM-MildMartin Heptode Join Date: Jan 2004 Location: Stockport, Greater Manchester, UK. Posts: 828	Re: Crystalling Pye PF85's. Or even a Baofeng for £30 or less. But it is economically viable, for receive only, on one channel on two identical high-quality ex-PMR units, which I think was what Robert B. was intending?

20th Sep 2012, 7:31 pm	#3
davidw Heptode Join Date: Sep 2006 Location: Woodbridge, Suffolk, UK. Posts: 643	Re: Crystalling Pye PF85's. Robert,according to Chris Loreks PMR Conversion book PF85 A1 and B2 sets receive crystal is :- Crystal Freq= (receive freq-10.7 Mhz)/3 so thats (162.025-10.7)/3 = 50.4417Mhz. Hope that helps. __________________ Dave G1AGK. My perception is my reality!

21st Sep 2012, 11:00 am	#7
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Re: Crystalling Pye PF85's. Indeed, there are two AIS frequencies on which vessels transmit identity and position data, and being in Falmouth I thought I'd give it a go. I've tried taking the audio output from a synthesised RX to my soundcard for decoding, but this is resulting in a high percentage of errors. For packet data work a discriminator tap is more reliable, and I don't wish to modify this rig (or tie it up on AIS when it's often used as a general 2 meters monitor). It also helps that I already have a PFX and PF85 on 70cms and a charger to accompany them, so a new pair of batteries are worth the £5 each they cost me. Getting a pair of crystals cut will be less than the cost of buying a new receiver (and potentially wrecking it trying to tap the discriminator) and far less than even a "budget" professional AIS decoder (prices start around £100). Many thanks for the crystal data, I shall report back as this proceeds. Regards, Rob __________________ Real radios glow in the dark M6GLD

29th Sep 2012, 9:38 pm	#8
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Re: Crystalling Pye PF85's. Further to the above, the sets have arrived and both appear to be in good shape. The batteries are recent replacements and hold their charge well, which is a nice bonus. One shall be crystalled for AIS reception here. The other I should like to crystal for channel 16 under my portable marine licence. I assume the transmit frequency for these is F/9, i.e. for 156.8 = 17.4222. I'd be greatful if this could be confirmed. My thanks and kind regards, Robs __________________ Real radios glow in the dark M6GLD

30th Sep 2012, 8:32 am	#9
davidw Heptode Join Date: Sep 2006 Location: Woodbridge, Suffolk, UK. Posts: 643	Re: Crystalling Pye PF85's. Not quite Rob, according to the same source as post#3 the A1 and B2 transmit is f/8 (the uhf versions are f/9) so for 156.8, Xf= 156.8/8=19.6Mhz. Both Chris Lorek's books are a must if you are into modifying ex PMR stuff. (no connection just a satisfied user) __________________ Dave G1AGK. My perception is my reality!

5th Oct 2012, 10:19 pm	#10
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Re: Crystalling Pye PF85's. I think I've got a PF85 service manual lurking about somewhere if you need more info. Alan.