Hovland Radia ServiceManual and Advice needed

[ovlov854]

Having newly acquired a Hovland Radia to accompany my Hovland Pre, I find that the signature blue backlighting does not work and th on/off lighting switch does not work although it clicks on and off.
Anyone know where i might be able to get a Service Manual from?

All else seems to work but the volume knob needs to be cranked up past 12 o'clock to get decent levels from phono and tuner :scratch:

[Blackdog]

I'm not 100% certain (it's been about 15 years since I saw a Radia), but I think the bulbs for the back lighting run off of a 24V supply. They may be wired in series, so if one goes, they all go.
Your gain issue may be one of input wiring. Do you have the balanced mod?

[ovlov854]

I'm not 100% certain (it's been about 15 years since I saw a Radia), but I think the bulbs for the back lighting run off of a 24V supply. They may be wired in series, so if one goes, they all go.
Your gain issue may be one of input wiring. Do you have the balanced mod?

My Radia only has XLR inputs. The pre-amp only has RCA. Therefore I use Cardas RCA/XLR adaptors with a RCA interconnect. Would that cause an issue?
What is the balanced mod?

[ovlov854]

On closer inspection of the owners manual..............it says not to use an unbalanced output from a preamp to the balanced input of the Radia. To do so will reduce the gain by a factor of 2 and reduce output power by a factor of 4
What about a properly wired pseudo balanced interconnect.......with the screen from the XLR connected to the negative of the RCA?
Any info on the balanced mod you referred to?

[Blackdog]

Balanced mod was the balanced inputs which you have. There was a later modification to install those on unbalanced amps.
I was just going to paste that part of the owners manual here for you, but I see you found it. Your so called pseudo balanced won't work either. It is still an unbalanced connection.
I hate that misleading term (pseudo balanced). It has been used to cheat people into thinking they are getting something balanced when they are not.

[Blackdog]

Here's a service note I have about the balanced inputs.
28709

[ovlov854]

Hi Dan..................Many thanks for your help and advice. Regards Martin

[Blackdog]

There is a service note on how to convert unbalanced to balanced. If I can find it, you can reverse it and make your amp unbalanced.
If I remember correctly, it isn't too complicated but it would require a tech to do it.

[ovlov854]

Hi Dan............would you be able to find me some detail on the backlighting bulbs if you have access to a service manual? Thanks a lot. I cannot find one here atm.

[Blackdog]

Your posts prompted me to go through some old documentation. No service manual for your amp, and no reference to those lamps at all.
If the wiring is similar to the HP100, then you may have a burnt resistor somewhere, or a burnt bulb.

I did find the documentation to convert unbalanced to balanced. The file is too big to upload though.

[ovlov854]

Once again many thanks for your help.

Now can anyone help me with finding a site to download the Service Manual??

[Blackdog]

There isn't one. When Hovland closed they put all their schematics on an ftp site and sent the link to their service people. That site closed when their subscription ran out.
Email me and I'll send you what I have.

[ovlov854]

Good News the Radia is fully functioning with the help of Mark at Malvern Audio Research and Blackdog of this parrish
My grateful thanks

[hifinutt]

wonderful news martin