RCA AR88D Comms Reciever

[Tedzed1]

I reckon you ought to get a half decent HRO next then I can chat about it 'till the cows come home.

Do you mean the HRO Senior, must say it seems an intriguing set, especially with all the plug in coils.
I have been looking around at different "boatanchors" lately, and must say I would quite fancy a Collins R-390-A, it looks very impressive.

Looks like I need to improve the bank balance, time to sell the kids.

[pwdrive]

Hi Paul, yes, the HRO Senior (the HRO Junior is rare over here, it was a stripped down version of the Senior) The Senior and the M, MX etc are for all intents and purposes the same, I think the MX has the Xtal within the phasing can, the Senior has a plug in Xtal on top of the phasing can and is much easier to clean should the need arise.
The next version time wise is the HRO 5 , the HRO 5t (t for table model) is aka the Reception set R106 MK11, electronically it's almost the same but it uses metal octal valves as opposed to the UX6 bases valves used in the Senior, MX, etc, the HRO 5t has a white "S" meter without illumination, the Senior has a yellow/orange meter which is illuminated, the white meter is scaled in m/a and the early meters are scaled in "S" units.
So far as I am aware the plug in coil packs are interchangable but if you obtain the coil packs seperately from another source they will need aligning to the receiver, the adjustments in the coil packs is by air spaced variable capacitors, all very easily accessable from the top of the chassis.
There are two types of coil pack (both interchangable) the General Coverage and the Bandspread, the bandspead coil packs cover the same as the general coverage but they have a bandspread option which is enabled by moving the contact screws on each coil pack can, the bandspread coil packs have two graph windows, the general coverage ones have one graph window and one logging window (white card) which you can jot down station details etc.
The bandspread coils go for more money than the general coverage ones, there are four bandspread coil packs for the full set, all other coil packs are general coverage, the bandspread coil packs are a joy to use when trying to resolve single signal reception and SSB on the amature bands.
The reduction drive on the HRO is well known and lives up to it's reputation, the anti backlash gears are cast not stamped out of thin brass etc.
There is a bit of a knack (easily learnt) when removing the tuning dial assy for cleaning/greasing etc the main thing to remember is that the outer surface of the main drive spindle bush (which is fixed) is eccentric to the main drive shaft, the inner dial (the one with the numbers on) slides on and rotates on the outer surface of the drive spindle bush and it has to be bang on otherwise the tuning mech. will start binding very badly, the basic trick is to rotate the tuning knob until the number "250" appears in the outer scale window, at that point the knob grubscrews can be removed and the whole assy, can be withdrawn, same for reassembly but on reassembley of the two halves of the tuning scale there is a pointer on the back which the gear teeth have to be aligned to, if all that is done ok then no problem, do it a couple of times and it gets quick to do. A word of caution with the HRO the output connector tags are both live when connected to a speaker matching transformer as is the B+ transmit relay link, also the pot shaft for the "S" meter set zero is live, if that pot is removed for what ever reason it must be replaced with it's chassis insulating washer otherwise shortie shortie. The B+ switch must be switched to off when changing the coil packs otherwise sparky sparky. I have a couple of HRO's in the Gallery. Early HRO's have round IF cans and are worth a bit, most HRO's you come across have square IF cans. Price wise you can pick a reasonable one up for servicing from around £70 to £120, probably a bit more if it has the bandspread coils, the coils seperately come up on Ebay quite often.

Lawrence.

[Yorkie]

YUM, now this I would certainly consider, especially at the start price.

http://www.ebay.co.uk/itm/Vintage-Racal-...7675.m1986&_trkparms=aid%3D555001%26algo%3DPW.CURRENT%26ao%3D1%26asc%3D29%26meid%3D3804428622007683756%26pid%3D100013%26prg%3D1013%26rk%3D4%26sd%3D180909274578%26

I must have caught the bug.

If you look at the 'service label' you'll see the initials 'R.F'. That will no doubt be Rob Filby ' Mr Racal' himself. Nothing he doesn't know about Racals, and anything he's had his mitts on will be bang on spec. Such complex receivers that without the proper test gear and knowledge how to use it, you can't even be sure if it's working right. Be interesting to see what it goes for - apart from the 'R.F' provenance, it looks excellent cosmetically - I doubt a better one will come to light in a hurry.

Nice to see an offering like that, rather than the usual 'don't know if it's working properly' offerings.

[Radio Fixer]

Enthusiasm is contagious and its starting to rub off on me. Browsing comms sets now. That Racal is just up the road from me . I had a quick read and other rack items are needed to do SSB operation for example. No I will refrain and it wil probably go for a fair price even though no bidding so far.

I have in front of me a March 1990 RB with a pic of a Restored Colins R390. I kept this mag 'cos I was so awed by the electronics and construction. It must be one of the most beautiful and complex valve receivers. If anyone is interested and not seen the article then I can scan it and post it as a PDF.

Gary (would luv to see one for real)

[pwdrive]

Collins 390A 'tis the holy grail for a lot of folk, including me, it is said that they were engineered to a specification and not a price.
Most comms. receivers will resolve upper and lower SSB without an adaptor quite adequately, having said that decent filters and a decent product detector will enhance resolvability, a lot is to do with tuning your ears to the transmission in question while mentaly rejecting any unwanted modulation that might be breaking through.
Some comms. receivers can be a bit daunting if a person is not familiar with them but it's like any other receiver, one block at a time, most of the early ones are just single conversion superhets with a BFO and an RF amp. maybe a simple filter.
Just a few more bands and just a bit heavier...
I would recomend getting one if anyone is interested in what the wild waves are saying.

Lawrence.

[pwdrive]

I have in front of me a March 1990 RB with a pic of a Restored Colins R390. I kept this mag 'cos I was so awed by the electronics and construction. It must be one of the most beautiful and complex valve receivers. If anyone is interested and not seen the article then I can scan it and post it as a PDF.

Yes Gary, that would be good.

Lawrence.

[Radio Fixer]

OK Lawrence, will do.

Tempted to make a bid on this (crazy or what). Lots on the Web about them and it would be my most challenging restore to date (depending how bad it is). Have loads of those valves, I think, in the loft. Wonder what it will go for?

http://www.bvws.org.uk/auctions/photos/w...-dec-2012/

cheers Gary

[pwdrive]

Gary, just opened the link, lot's of photo's, which one are you refering to ?

Lawrence.

[Radio Fixer]

Oh! sorry thought it would go straight there, as I had the page expanded. Its Lot 20, the Hallicrafters Skyrider Sx28. Like the style of it... might even be allowed to display it for a while ... assuming I can get it going!

Here's the PDF. What a piece of electronics ...


  R390A.pdf (Size: 4.37 MB / Downloads: 597)

Gary

[AlanBeckett]

Is anybody going?
There's a couple of things I'd like to bid on but I can't make it

Alan