Yes. Thank you, Jim. Second quarter 2017 end user net revenues were $15.1 million or 95% of net revenues; compared to $12.5 million or 88% of net revenues in the first quarter. OEM net revenues were $762,000 or 5% of net revenues; down from $1.7 million or 12% for the first quarter.
Net revenues for markets out side of the ATE market were $5.7 million or 36% of net revenues; compared with $3.7 million or 26% of revenues in the first quarter. As noted earlier in this call, Ambrell net revenues for the second quarter were 2 million. And our net revenues for markets outside of the ATE market, excluding Ambrell, were 3.7 million or 24% of net revenues. So clearly, Ambrell does further diversify our served markets. We expect that revenues from markets outside of the ATE will equal or excess our ATE market revenues going forward.
Our second quarter gross margin was $8.4 million or 55% as compared with $7.7 million or 55% in the first quarter. The reduction in gross margin was primarily the result of an increase in our fixed manufacturing costs and a less favorable absorption of these costs; partially off set by a decrease in our consolidated component material costs, which declined from 33.2% in the first quarter to 32.8% in the second quarter.
Our fixed manufacturing costs increased by $444,000 or 31% sequentially. And represented 12% of our net revenues in the second quarter; compared to 10% in the first quarter. Ambrell's fixed manufacturing costs were $404,000. And excluding the impact of Ambrell, our fixed manufacturing costs would have only increased $40,000 or 3% sequentially, and would represent 9% of our net revenues for the second quarter. The increase in second quarter fixed manufacturing costs was primarily the result of increased cost for insurance.
The decrease in our component material cost was driven - was driven by a reduction in the component material costs of our EMS segment, which declined from 35.1% in the first quarter to 32.7% in the second quarter, due to a more favorable product mix which reflected a much higher level of docking (hard rush) sales in the second quarter as compared with the first. This improvement was partially off set by an increase in the component material cost of our thermal segment, which grew from 31.7% in the first quarter to 32.9% in the second quarter.
This increase was due to a less favorable product mix in the second quarter, as compared to the first. Excluding the impact of the acquisition of Ambrell, our second quarter growth margin, would have been 7.5 million dollars or 54%. Ambrell second quarter, 2017 gross margin was 49%. Selling expense was 1.9 million to the second quarter, compared to 1.7 million in the first quarter -- an increase of $203,000 or 12%.
Second quarter selling expense included $317,000 for Ambrell. Excluding this amount our second quarter selling expense would have been $1.6 million dollars, which was $114,000 or 7% sequential decrease. The reductions were primarily related to lower levels of sales travel and commission. Engineering and product development expense was $982,000 for the second quarter, compared to $935, 000 for the first quarter -- an increase of $47,000 or 5% sequentially.
Second quarter engineering and product development expense included $82,000 for Ambrell. Excluding this amount our second quarter, engineering and product development expense would have been, $900,000, which was at $35,000 or 4% decrease sequentially. The reduction was primarily related to lower levels of salary and benefit costs in our EMS segment, and reduced patent legal costs, which were partially offset by increase spending on development materials by our thermal segment.
General and administrative expense grew from $2 million dollars in the first quarter, to $3.3 million dollars in the second quarter -- an increase $1.3 million, or 65%. Included in the second quarter GNA expense was $849,000 of transaction costs related to the acquisition of Ambrell, and $536.000 of G&A costs for Ambrell. Excluding these amounts, our second quarter G&A expense would have been $1.9 million, which was a $92,000 or 5% sequential decrease.
The decrease primary the result of lower levels of salary and benefit costs in our corporate segment, and reduced travel costs. These reductions were partially offset by increases in officer and staff bonuses accruals. Other income was $54,000 in the second quarter, compared to $41,000 in the first quarter, an increase of $13,000 or 32%.
Included in other income for the second quarter was $12,000 of forex transactions gains for Ambrell; excluding this amount, second quarter other income would have been $42,000 which was an increase of $1,000 or 2% sequentially. We accrued an income tax expense of $891,000 in the second quarter, compared to $1.1 million accrued in the first quarter. Our effective tax rate increased to 38% in the second quarter, from 35% in the first quarter.
The increase in our effective tax rate primarily reflects not recording tax benefits on losses incurred in Ambrell's European operations, as we don't expect to be able to utilize them due to expected changes in our operating structure.
At June, 30, 2017, we had a deferred tax liability of $4.1 million, compared to a differed tax asset of $1.1 million as of March, 31, 2017. The acquisition of Ambrell brought over $1.8 million of differed tax liabilities, which we are in the process of evaluating as part of our purchase price allocation work, which is on going.
In connection with our quarter closing, and the estimates we have created for Ambrell, we established at $3.4 million differed tax liability, related to the estimated and tangible assets, we have primitively determined for Ambrell. Offsetting these differed tax liabilities was a $1.1 million differed tax asset. We expect our tax rate for the balance of 2017, to be in the range of 35 to 37%.
On a gap basis, second quarter net earnings, were $1.4 million, or 14 cents per diluted share, compared with first quarter net earnings of $2.1 million or 20 cents per diluted share. On a non gap basis, second quarter adjusted net earnings, we're $1.7 million, or 16 cents per diluted share, compared with first quarter adjusted net earnings of $2.1 million or 21 cents per diluted share. Diluted average share is outstanding, worth $10, 334,894 on June, 30th.
During the second quarter we did not issue or repurchase any shares. As of June, 30, 2017 we have repurchased accumulative total of $297,000 (owe to owe) shares, or approximately 2.8% of our outstanding common stock, and at a net cost of $1.2 million or $4 per share. Average depreciation and appreciation expense, was $373,000 for the second quarter compared to $150,000 from the first quarter.
Acquired in tangible amortization, was $249,000 in the second quarter, an increase of $196,000 from the first quarter. And the increase in tangible amortization was related to the acquisition of Ambrell.
As I noted previously, we have not yet completed our purchase price allocation for Ambrell and we expect the amount of quarterly amortization to increase in the third quarter, as we reflect a full quarter of Ambrell's operations.
EBITDA was $2.7 million for the second quarter, down $614,000 or 18% from the $3.3 million in EBITDA reported for the first quarter. Consolidated head count at the end of June, which includes temporary staff, was 217, an increase of 123 staff from the level we had at March 31st. Included in the June total, with 93 Ambrell staff and adjusted for this amount, our staff would be 124 at the end of June, up one from the end of March.
I will now turn to our balance sheet. Cash and cash equivalents at the end of the second quarter were $7.6 million, down $19.6 million from March 31st. We used $23.2 million in cash for the Ambrell transaction to fund the purchase price and pay transaction related expenses. We currently expect cash and cash equivalents to increase throughout the balance of 2017.
Accounts receivable increased to $11.9 million at June 30th, an increase of $2.1 million sequentially. Included in this amount was $3.4 million for Ambrell. Adjusted to exclude this amount, accounts receivable would have been $8.6 million, an increase of $3.2 million or 59% sequentially. The increase in receivables was related to increased sales in to Asia, where credit terms are longer than in other parts of the world.
Inventory increased $2.3 million to $6.2 million at the quarter end. Included in this amount was $1.9 million for Ambrell. Adjusted to exclude this amount, inventories would have been $4.3 million, an increase of $608,000 or 17% sequentially. The growth in inventories was in response to expected shipments in the third quarter.
Capital expenditures during the second quarter were $89,000, down from $114,000 in the first quarter. Included in the second quarter capital expenditures was $7,000 for Ambrell.
Bob provided consolidated and segment revenues and booking data earlier. The backlog at the end of June was $11.1 million, up from $8.2 million at the end of March. Included in June 30th backlog was $4.4 million for Ambrell. Excluding this amount, backlog would have been $6.6 million, down $1.6 million from the end of March.
In terms of our financial outlook, as noted in our earnings release, we expect that net revenue for the quarter ended September 30, 2017 will be in the range $17.5 million to $18.5 million and that net earnings will range from 12 cents to 16 cents per diluted share.
We currently expect that our Q3 2017 product mix will be less favorable, as compared with the second quarter, and that the third quarter gross margin will range from 48 to 50%. Operator, that concludes our formal remarks, we can now take questions.