Robyn Model 500 a
I'm looking for any help I can get for this rig, I have spent 2 hours looking for a manual with no luck. I thought it was a SBE 36 but there are some differences in the transmit section. I'm looking for a schematic or manual that would help me solve my problem. When testing the transmitter the finals 6kd6's want to occilate. Tried new tubes but didn't help. Any help would be appreciated. TNX. 73's.
Is it a tube ham rig or a CB? I know Robyn only made CB rigs. Dont know about ham rigs made by them. Do you have a pic to show everyone? Im curious about your rig.
Robyn 500 a
It is a hybred, the final section takes 2 6KD6 with a 12by7 as the driver, all other components are transister. It is a Ham radio 10 thru 80 meters. All the coils are taped in the right places. It looks like a SBE 36 and it is ditigal, has a seperate power supply. I don't have any pic's.
The Robyn 500 came out in 1970. The only information that I have on the unit is just the basic specifications:
500 watt INPUT PEP SSB, 400 watt INPUT CW.
0.1 kHz "readout" using "Nixie" tubes
Built-in noise blanker
High sensitivity Schmidt-trigger VOX
0.5 microvolt sensitivity for 10 dB S+N/N ratio
2.4 kHz selectivity at 6 dB
Image and IF rejection 50 dB
Carrier suppression 40 dB
Sideband suppression 50 dB
USB, LSB, CW operation
CW filter available as an option
Original price including separate power supply/speaker $895.00
There was a post about a year or two ago about the Robyn 500A. At that time I believe it was determined that the Robyn 500A and the SBE 36 were one and the same. I don't remember any details as which came first. I seem to remember that the documentation was interchangable, and was in the sam's photofac's. Search the archives and see what you find.
ISTR . . . .
I remember seeing an ad for the Robyn, and I think that SBE had it re-badged for them as the SB-36. Gee, I miss those Nixie readouts -- and the fact they're almost impossible to find when they go bad. Maybe that's why they invented LCD and LED readouts . . .
Sounds like all you need is neutralization; that should be easy to find: look for a variable cap that goes from final plates to the low (cold?) side of the grid coil. They're usually hot with plate voltage, so use an insulated diddle stick to adjust it.
Either way, you've got a really rare radio on your hands. I don't remember SBE selling many 35's and 36's, compared to the 33's and 34's.
Robyn 500 a
Well gentlemen the Robyn 500 A is alive and well. I finally broke down and ordered a SB36 manual from Vintage manuals. The Robyn is the same as the SB 36. The caps have been replaced, a soft start installed, new power cord( the original was like a lamp cord and would not handle the power. New finals and driver( someone had used a 12BY7 as the driver WRONG) MANY, MANY,MANY transistors and many ,many,other parts.I fired it up the other day and got a 5 9 signal report from CA. and a 5 3 from MA. I'm showing about 300 watts out. It works very well. Now I need to know what it's worth because I'm going to sell the rare jewel. Any takers??????? Tnx for all your help.
Just for info here is a link to a photo of an SBE SB-36.
I've just added the Robyn 500 to my database. If anyone has more specs / images / etc. please let me know.