This is the last of the radios given to me by Jerry: See posts below.

In 1928 Sparton (Sparks Withington) was still at odds with RCA over radio pattents. Without rehashing information that can be found elsewhere: http://spartonequasonne.webs.com/models.htm
I will give you some breif highlights of this Equasonne version.

First, I consider it a true Equasonne and by that I mean that it does not incorporate the RF stage added to later units - which really was an attempt to improve on the shortcommings of the Equasonne design and really was consideration for the possible infringement of the TRF design that Sparks was trying to skirt. And it also lacked the first AF stage that was added to some models, like my 930 (mentioned on the web page above). This modification basicly added a 484 or 485 triode to boost input to the audio final(s).

On this note it is important to consider the tubes that were used in these radios. Again, trying to dodge RCAs pattents, Sparks used their own tubes which were really only slightly different than RCA's with the significant difference being filament voltages.

So the 69 is an AC powered table-top radio, very similar or exactly like the chassis used in consoles. This makes the chassis a tight fit. Especially when you consider how the modules are connected.

There are 3 basic modules in all Equasonnes with the rare addition of the audio stage mentioned above. In the back is the power supply/audio amp, front left, the passive tuner (no RF amplification) and then, on the front right, the RF/detector module.

As mentioned, and a serious consideration prior to undertaking any sparton Equasonne restoration is the fact that the cost of the radio is little compaired to the cost of the stock, Sparton/Cordon tubes. This version uses a Sparton 585 as the only audio stage following the detector. Now, for all practical pourposes a 585 is the same as a 250 which only slightly improves on the chances/cost of finding one if yours is missing. The other triodes are 485 (or 484s) which were easy to find and cheap but that is changing too. For practical pourposes a 56 can be used, NOT a 27, though this can affect the tuning of the already finicky RF stage. Read more on the site above on Sparton's suggestion for strong or weak tube placement.

The most significant issure with this radio, other than the fact that all of the tubes were missing or wrong (27s), was the failure of the power transformer. At some time three of the 484s were replaced with 27s. This could have lead to, or at least contributed to the failure. Anyway one half of the HV winding was shorted.

I found a replacement on E-Blah. It had the same problem. The nice fellow refunded it;s cost. Having two inspired me to attempt a rewind. Replacements are few since the wierd filament voltages, 5, 7.5 and 3 are not standard on any other manufacture's radios.

The transformer I got off of the auction site had been heated so much that the windings has seperated since the tar and bee's wax had all melted out. It was easy to remove the HV from the center of the stack, inspect the primary and filament windings and then replace the HV with one I made. Well I measured the wire size and ohmed out the good side of the center tapped HV winding and got 324 ohms. A little consultation of the magnet wire chart got me going on a new one. This worked BUT I must have misjudged the wire size by one gague and ended up with a 450-0-450 volt B+ winding.

It would have worked. It needed about a 16k resistor but at about 50W - really big! So I moved on to the original transformer, knowing now what I did wrong. To make it a short story, I was sucessfull, though this one required some time in the oven to take apart. It was now at 325-0-325 volts for the HV prior to loading.

I could now move on to recaping the unit.

The biggest challenge in recaping the RF section is the odd construction of the original capicators and as usual, I wanted to keep the factory look. In the photo - 2 above - you see the tubular like things on the RF board. All but one of them is a 1uf cap. On the Equasonne page listed above he has a process that can be used. It was adapted for restuffing because a single replacement cap would not fit inside of the original.

I found that it was much easier to use two .47uf caps allowing me to leave the support rod intact. This also made the part much sturdier.

Fortunatly all of the other "iron" was still good.

There is one other thing I should mention for all Equasonnes, especially this model. That is the grounding of the modules which most might assume is accomplished by the multiconductor cable - but no!

Above is sparton's ground system for later Equasonne models which was not used on the 69.

On this radio the most convenient way to ground all three modules togeather (required) is to strap them togeather at the mounting bolts.

Though there were reminents of this type of connection prior to disassembly, I can't be sure that this is what the factory did - but I think that it is correct.

The design of the cabinet keeps these bolts and wire off of the table top. So unless something is dragged across the bottom the ground is rather safe. Opperation of the unit whithout this ground results in motorboating and other undesireable noises.

In conclusion, I find this radio to be an average/acceptable performer. Considering the design it is acctually superior to what you might expect and better than most of the 5 tube screen-grid models that drive a 245 by resistance coupling to the 224 detector.

This is the last console from the collection of radios given to me  by Jerry. It is a 12 tube super with AFC and the popular Teledial.

The cabinet design makes it a perfect fit for the corner of a room. It is large, nearly as big as the GE M-125 pictured several posts below.

The main attraction for most people is the "Teledial" or push button tuning. This function works much like the similar configurations on other brands such as the Philco 37-116. The most notable difference is that the Grunow uses a discriminator/detector and AFC which works very well when using the push-and-turn tuning unlike the "Magnetic Tuning" on the Philco that works - sometimes - and is relatively hard to calibrate.

The Grunow's tone control has 6 positions, or 2 sets of low, medium and high tone. The difference between the normal and "Dial" settings is the activation of the AFC allowing aproximate tuning using the Teledial which then is automaticly adjusted to a medium to strong pre-set station. Again, as a compairison to the Philco which works for strong stations.

The Grunow 1291B cabinet has rounded sides making it a great fit in corners of a room. The veneers used are quite striking and the gold-toned accent above the black band at the base, is a novel and nice touch. From reasearch I have done, I believe  that the black base which has the same veneer beneith the paint, was not always painted when it left the factory. This one was definatly black so it was restored that way.

I would say that this cabinet design was lacking in some aspects. Support and alignment of the curved sides seemed to be a problem. As found, very few of the blocks used to secure the sides to the base and radio shelf were still attached and even when they are there are large gaps making the glue joints less than ideal.

The curved veneers and backing have no trim on the front edges which exposes the veneer edge to likely damage/pealing. Also this design places a lot of stress on the curved wood its self and without better attachment the edge that meets the front pannel (where the teledial/knobs are) tends to open up allowing for a visable crack. I took a lot of time to squar-up the cabinet to reduce the impact of these deficiancies.

I was able to reuse the original grill cloth.

I would reccomend removing the chassis prior to moving this radio unless care in handling can be assured.

One of the major issues with the restoration of this chassis was damage to the 3 position Band switch which is delt with in detail several posts below.

This 12 tube chassis uses push-pull 6F6s for strong audio with good bass with the 12 inch field coil speaker.There is a 5Z3 rectifier which was also a good choice for stable B+. There is no Eye tube or other signal strength indicator. A 6J7 is used as the AFC control. All but the rectifier are metal tubes.

Unfortunatly some of the paper caps had already been changed out in a previous service. So I will be looking for original replacements to re-stuff. I also had to replace the output transformer since one-half of the primary was open.

The tuning knob moves the entire dial assembly with ease as long as the chassis is positioned in the cabinet correctly. A strip of brown felt is attached to the edge if the dial cut-out to improve appearance and allow for slight contact off the rotating assembly though up/down, in/out and right left adjustment of the chassis is particulary important for this dial to function properly.

As I tuned the presets I orientated the buttons with stations assigned to appear level when at the 180 deg position. Unasigned buttons are at random positions relative to the dial. They can be manipulated but only after removing the dial cover (6 screws). The station labels are not accurate, rather the ones that came with the set.

The question was: What setting controls the AFC?

Pictured are the lower two controls - knobs.
On the right we have the band selector: F=Foreign, B=Broadcast, P=Police.
On the left is a combo-function control: STD=No AFC with either Low, Medium or High tone control.
Dial=AFC On with either Low, Medium or High tone control.

It should be noted that manual or pushbutton tuning will work in either STD (AFC of) or Dial (AFC on). If the pushbutton tuning is used with the AFC off (STD) weak stations may need manual fine tuning due to errors caused by lash or even centrifical force (the tuner misses its mark).

A few of the Emersons:

Philco 37-116

And a couple of Zenith Chair-sides:

I have finally reached the bottom of the "radio pile". See the story and other radio below. So I have some time to catch up on a few things. One of those has been the promis to update the pictures of the display. The pictures on the home page are several years old. Many of the new additions have been posted here on the blog but now you can see how they are displayed.

This is only the upper level display. I will add a few more of the lower level soon and there are still 3 more radios not yet posted from the "pile".

I'll move some of these to the home page soon but for the moment you can go there and see the "before" pictures as well.